Betterment Resources | Original Content by Financial Experts

Betterment's Socially Responsible Investing portfolios methodology

Betterment's tax-loss harvesting methodology

The Goldman Sachs Smart Beta portfolio methodology

How Betterment manages risks in your portfolio

How Betterment manages risks in your portfolio Jun 16, 2026 12:00:00 AM Betterment’s tools can keep you on track with the best chance of reaching your goals. Investing always involves some level of risk. But you should always have control over how much risk you take on. When your goals are decades away, it's easier to invest in riskier assets. The closer you get to reaching your goals, the more you may want to play it safe. Betterment’s tools can help manage risk and keep you on track toward your goals. In this guide, we’ll: Explain how Betterment provides allocation advice Talk about determining your personal risk level Walk through some of Betterment’s automated tools that help you manage risk Take a look at low-risk portfolios The key to managing your risk: asset allocation Risk is inherent to investing, and to some degree risk is good. High risk, high reward, right? What’s important is how you manage your risk. You want your investments to grow as the market fluctuates. One major way investors manage risk is through diversification. You’ve likely heard the old cliche, “Don’t put all your eggs in one basket.” This is the same reasoning investors use. We diversify our investments, putting our eggs in various baskets, so to speak. This way if one investment fails, we don’t lose everything. But how do you choose which baskets to put your eggs in? And how many eggs do you put in those baskets? Investors have a name for this process: asset allocation. Asset allocation involves splitting up your investment dollars across several types of financial assets (like stocks and bonds). Together these investments form your portfolio. A good portfolio will have your investment dollars in the right baskets: protecting you from extreme loss when the markets perform poorly, yet leaving you open to windfalls when the market does well. If that sounds complicated, there’s good news: Betterment will automatically recommend how to allocate your investments based on your individual goals. How Betterment provides allocation advice At Betterment, our recommendations start with your financial goals. Each of your financial goals—whether it’s a vacation or retirement—gets its own allocation of stocks and bonds. Next we look at your investment horizon, a fancy term for “when you need the money and how you’ll withdraw it.” It’s like a timeline. How long will you invest for? Will you take it out all at once, or a little bit at a time? For a down payment goal, you might withdraw the entire investment after 10 years once you’ve hit your savings mark. But when you retire, you’ll probably withdraw from your retirement account gradually over the course of years. What if you don’t have a defined goal? If you’re investing without a timeline or target amount, we’ll use your age to set your investment horizon with a default target date of your 65th birthday. We’ll assume you’ll withdraw from it like a retirement account, but maintain a slightly riskier portfolio even when you hit the target date, since you haven’t decided when you'll liquidate those investments. But you’re not a “default” person. So why would you want a default investment plan? That’s why you should have a goal. When we know your goal and time horizon, we can determine the best risk level by assessing possible outcomes across a range of bad to average markets. Our projection model includes many possible futures, weighted by how likely we believe each to be. By some standards, we err on the side of caution with a fairly conservative allocation model. Our mission is to help you get to your goal through steady saving and appropriate allocation, rather than taking on unnecessary risk. How much risk should you take on? Your investment horizon is one of the most important factors in determining your risk level. The more time you have to reach your investing goals, the more risk you can afford to safely take. So generally speaking, the closer you are to reaching your goal, the less risk your portfolio should be exposed to. This is why we use the Betterment auto-adjust—a glide path (aka formula) used for asset allocation that becomes more conservative as your target date approaches. We adjust the recommended allocation and portfolio weights of the glide path based on your specific goal and time horizon. Want to take a more aggressive approach? More conservative? That’s totally ok. You’re in control. You always have the final say on your allocation, and we can show you the likely outcomes. Our quantitative approach helps us establish a set of recommended risk ranges based on your goals. If you choose to deviate from our risk guidance, we’ll provide you with feedback on the potential implications. Take more risk than we recommend, and we’ll tell you we believe your approach is “too aggressive” given your goal and time horizon. Even if you care about the downsides less than the average outcome, we’ll still caution you against taking on more risk, because it can be very difficult to recover from losses in a portfolio flagged as “too aggressive.” On the other hand, if you choose a lower risk level than our “conservative” band, we'll label your choice “very conservative.” A downside to taking a lower risk level is you may need to save more. You should choose a level of risk that’s aligned with your ability to stay the course. An allocation is only optimal if you’re able to commit to it in both good markets and bad ones. To ensure you’re comfortable with the short-term risk in your portfolio, we present both extremely good and extremely poor return scenarios for your selection over a one-year period. How Betterment automatically optimizes your risk An advantage of investing with Betterment is that our technology works behind the scenes to automatically manage your risk in a variety of ways, including auto-adjusted allocation and rebalancing. Auto-adjusted allocation For most goals, the ideal allocation will change as you near your goal. Our automated tools aim to make those adjustments as efficient and tax-friendly as possible. Deposits, withdrawals, and dividends can help us guide your portfolio toward the target allocation, without having to sell any assets. If we do need to sell any of your investments, our tax-smart technology is designed to minimize the potential tax impact. First we look for shares that have losses. These can offset other taxes. Then we sell shares with the smallest embedded gains (and smallest potential taxes). Rebalancing Over time, individual assets in a diversified portfolio move up and down in value, drifting away from the target weights that help achieve proper diversification. The difference between your target allocation and the actual weights in your current ETF portfolio is called portfolio drift. We define portfolio drift as the total absolute deviation of each super asset class from its target, divided by two. These super asset classes are US Bonds, International Bonds, Emerging Markets Bonds, US Stocks, International Stocks, and Emerging Markets Stocks. For Betterment-constructed portfolios that include a cash allocation, drift in the cash allocation is measured alongside super asset class drift. (Separately, Betterment-managed custom portfolios evaluate drift at the security group level. For reference, security groups are groupings of tickers that include a primary ticker, and may include secondary and/or tertiary tickers designed to help avoid wash sales and allow for tax-loss harvesting opportunities). A high drift may expose you to more (or less) risk than you intended when you set the target allocation. Betterment automatically monitors your account for rebalancing opportunities to reduce drift. There are several different methods depending on the circumstances: First, in response to cash flows such as deposits, withdrawals, and dividend reinvestments, Betterment buys underweight holdings and sells overweight holdings. This reactive rebalancing generally occurs when cash flows going into or out of the portfolio are already happening. We use inflows (like deposits and dividend reinvestments) to buy asset classes that are under-weight. This reduces the need to sell, which in turn reduces potential capital gains taxes. And we use outflows (like withdrawals) by seeking to first sell asset classes that are overweight. Second, if cash flows are not sufficient to keep a client’s portfolio drift within its applicable drift tolerance (such parameters as disclosed in Betterment’s Form ADV), automated rebalancing sells overweight holdings in order to buy underweight ones, aligning the portfolio more closely with its target allocation. This proactive rebalancing reshuffles assets that are already in the portfolio, and requires a minimum portfolio balance (clients can review the estimated balance at www.betterment.com/legal/portfolio-minimum). The rebalancing algorithm is also calibrated to avoid frequent small rebalance transactions and to seek tax efficient outcomes, such as helping to reduce wash sales and minimizing short-term capital gains. Allocation change rebalancing occurs when you change your target allocation. This sells securities and could possibly realize capital gains, but we still utilize our tax minimization algorithm to help reduce the tax impact. We’ll let you know the potential tax impact before you confirm your allocation change. Once you confirm it, we’ll rebalance to your new target with minimized drift. When Betterment rebalances a portfolio with a cash allocation, the rebalancing algorithm will first seek to bring the portfolio's cash allocation back to its target before investing in securities. If cash is below its target allocation, rebalancing will first use available funds (e.g., deposits, dividends, and/or proceeds from selling overweight holdings) to increase cash up to target, and only any remaining available cash is invested in securities; conversely, if cash is above its target allocation, the excess cash above target will be invested in securities as a part of the rebalancing transaction. If you are an Advised client, rebalancing in your account may function differently depending on the customizations your Advisor has selected for your portfolio. We recommend reaching out to your Advisor for further details. For more information, please review our rebalancing disclosures. How Betterment reduces risk in portfolios Investments like short-term US treasuries can help reduce risk in portfolios. At a certain point, however, including assets such as these in a portfolio no longer improves returns for the amount of risk taken. For Betterment, this point is our 60% stock portfolio. Portfolios with a stock allocation of 60% or more don’t incorporate these exposures. We include our U.S. Ultra-Short Income ETF and our U.S. Short-Term Treasury Bond ETF in the portfolio at stock allocations below 60% for both the IRA and taxable versions of the Betterment Core portfolio strategy. If your portfolio includes no stocks (meaning you allocated 100% of your portfolio’s investments to bonds), we can take the hint. You likely don’t want to worry about market volatility. So in that case, we recommend that you invest everything in these ETFs. At 0% stocks, a Betterment Core portfolio generally consists of 60% U.S. short-term treasury bonds, 20% U.S. short-term high quality bonds, and 20% inflation protected bonds.* Increase the stock allocation in your portfolio, and we’ll decrease the allocation to these exposures. Reach the 60% stock allocation threshold, and we’ll remove these funds from the recommended portfolio. At that allocation, they decrease expected returns given the desired risk of the overall portfolio. Short-term U.S. treasuries generally have lower volatility (any price swings are quite mild) and smaller drawdowns (shorter, less significant periods of loss). The same can be said for short-term high quality bonds, but they are slightly more volatile. It’s also worth noting that these asset classes don’t always go down at exactly the same time. By combining these asset classes, we’re able to produce a portfolio with a higher potential yield while maintaining relatively lower volatility. As with other assets, the returns for assets such as high quality bonds include both the possibility of price returns and income yield. Generally, price returns are expected to be minimal, with the primary form of returns coming from the income yield. The yields you receive from the ETFs in Betterment’s 0% stocks portfolio are the actual yields of the underlying assets after fees. Since we’re investing directly in funds that are paying prevailing market rates, you can feel confident that the yield you receive is fair and in line with prevailing rates. Work toward your financial goals without risking it all Choosing an investment portfolio is a personal decision, but it doesn’t have to be a difficult one. At Betterment, our goal is to help you feel confident that you’re always taking an appropriate amount of risk. We’ll help you select a portfolio with the risk level that’s right for you, and you can rest assured that our automated services are built to manage it efficiently. *Target investments, actual holdings will vary.

Three blockbuster IPOs are launching. Here's when they'll land in your portfolio.

Three blockbuster IPOs are launching. Here's when they'll land in your portfolio. Jun 15, 2026 5:20:03 PM SpaceX, OpenAI, and Anthropic are going public and selling billions in stock. Before you chase the buzz, read up on the backstory. Key takeaways Several high-profile, private companies are going public in 2026, headlined by SpaceX, OpenAI, and Anthropic. Many major indexes will fast-track these companies for inclusion within weeks of their debuts. The S&P 500, however, requires a year of seasoning and strict profitability criteria. Betterment customers have multiple on-ramps to invest in them via both automated and self-directed investing. IPO excitement can inflate opening prices, which makes it hard to come out ahead. There's a case for letting the market do its stress-testing first. As these mega-cap companies join an already tech-heavy market, diversification across sectors and geographies matters more than ever. The aerospace juggernaut SpaceX smashed records with its recent initial public offering (IPO), turning a slice of the once-private company's trillions in theoretical valuation into real, tradeable stock. It raised plenty of capital—and questions—in the process, so let’s dive in and sort through what it all means for everyday investors like yourself. Wait, what’s an IPO again? An IPO is when a privately-held company goes public, selling ownership in the open market as a way to both raise money and give earlier investors a chance to “exit” and realize a return. A trio of splashy technology IPOs headline this year: not just SpaceX, but two of the biggest brand names in AI: OpenAI and Anthropic. Both are targeting IPOs for later in 2026. Taken altogether, the three could be worth more than $3 trillion, though only a portion of that value will initially come to market. That public stock would still be substantial, so the companies and their underwriters are being deliberate about how many shares they offer upfront. Before we get to how many, however, let's look at the more pressing question: how soon might these newly-public companies show up in your portfolio? Indexes are fast-tracking the trio for inclusion, with one BIG exception Stock indexes are simply lists, or put another way, they’re the ingredient lists that index funds base their allocations on. These index funds can provide a cheaper and easier way to diversify, letting you passively invest with the aim of matching market returns. But the lists themselves aren’t open-sourced. They’re strictly owned and operated, with specific rules for how quickly new businesses on the block can gain entry. Mega-cap companies (those with valuations of $200 billion or more) are testing the limits of those rules. These tech companies could make their way into many notable indexes within weeks, if not days, of going public—including the Russell 1000, with $2 trillion of funds tied to it, and the CRSP US Large Cap Index, with $1.8 trillion indexed. But the mother of all indexes, the S&P 500, isn’t budging. It represents nearly half the value of all the investable stocks in the world, and nearly $12 trillion worth of funds follow its script. And those big institutional investors aren’t keen on passively buying brand new stocks whose valuations haven’t been stress-tested. The S&P 500 has strict profitability rules companies must pass before being eligible for inclusion, rules created after the dot-com bubble, and a 12-month waiting or “seasoning” requirement to boot. So how does all of this translate into your investing? Betterment customers can set their own launch window These IPO darlings will take a while to show up in the S&P 500, but Betterment customers still have several avenues for investing in them sooner rather than later. Most of our expert-built, curated portfolios—Value Tilt, Innovative Tech, Socially Responsible Investing, and Goldman Sachs Smart Beta—utilize index funds that have a higher likelihood of listing these companies within weeks of them going public. Our Core portfolio, on the other hand, primarily gets its U.S. stock exposure through funds that track S&P indexes, so inclusion will come farther down the road. If you self-direct your investing at Betterment, you can buy applicable funds themselves, or in many cases you can buy the companies directly as single stocks shortly after they begin trading. And in the coming weeks, we’ll also be introducing Custom portfolios, which pair the flexibility of self-directed investing with the power of our automation and tax-saving technology. This new investment option will replace our Flexible portfolio and let investors slot those funds or single stocks into their portfolios themselves. All this being said, trading in these freshly-minted equities often comes with heightened volatility and additional risk. The buzz and buildup to their IPOs can drive up their opening prices, making it tough to exceed expectations and net out in the positive. Morningstar, for one, believes SpaceX’s initial offering was overvalued. There's no shame in waiting for these companies to organically work their way into a globally-diversified portfolio. In fact, there's a strong argument for it. By then, you’d be buying at a price the market has had time to test, and you’d own them as part of a portfolio that doesn’t hinge on any single rocket launch. The tech-centric stock market is about to get more techy Diversifying across continents and industries is all the more important given the increasing concentration of the stock market. Technology already accounts for more than 44% of the S&P 500, and the arrival of several mega-cap tech and tech-adjacent IPOs in 2026 could push that share even higher. Fortunately, the full value of these companies won’t be going public. They’ll make a portion of shares available to the public in what’s known as “float,” with the remaining still owned by company insiders, employees, and the angel investors and venture capitalists who helped fund early stages of growth. SpaceX, for example, offered “only” $85.7 billion of shares in its IPO. It’s this public stock that informs how big a slice of indexes they’ll make up, and that number is still sizable. Increased concentration in any single sector, especially one driven by a relatively small number of mega-cap names, can amplify both gains during favorable market conditions and drawdowns during corrections. But that’s why Betterment exists. We’re here to do the heavy lifting of asset allocation, and help you sleep a little more soundly, no matter what starry-eyed headlines these IPOs generate.

Betterment’s portfolio construction methodology

Betterment’s portfolio construction methodology Jun 15, 2026 12:00:00 AM Learn more about the process that underpins all the portfolios we build on behalf of customers. Table of contents Introduction Global diversification and asset allocation Portfolio optimization Tax management using municipal bonds The Value Tilt portfolio strategy The Innovative Technology portfolio strategy The Socially Responsible Investing portfolio strategies Conclusion Citations I. Introduction Betterment builds investment portfolios designed to help you make the most of your money and live the life you want. This guide lays out our portfolio construction process, one informed by real-world evidence and systematic decision-making. The Betterment Core portfolio serves as the foundation for all of the globally-diversified portfolios we construct. From there, specific adjustments are applied to other portfolios based on the investment objective of their particular strategies. These adjustments include additional allocations to value-focused or innovative stocks, or adherence to Socially Responsible Investing (SRI) criteria. For more information on the third-party portfolios we offer, such as the Goldman Sachs Smart Beta portfolio, see their respective pages and disclosures. When building a portfolio, any investment manager faces two main tasks: asset class selection and portfolio optimization. We detail our approach to these in the sections that follow. Our fund selection process, while equally as important, is covered in a separate methodology. II. Global diversification and asset allocation An optimal asset allocation is one that lies on the efficient frontier, which is a set of portfolios that seek to achieve the maximum objective for any given feasible level of risk. The objective of most long-term portfolio strategies is to maximize return for a given level of risk, which is measured in terms of volatility—the dispersion of those returns. In line with our approach of making systematic decisions backed by research, Betterment’s asset allocation for the invested (non-cash) portion of portfolios is based on a theory by economist Harry Markowitz called Modern Portfolio Theory.1 A major tenet of Modern Portfolio Theory is that any asset included in a portfolio should not be assessed by itself, but rather, its potential risk and return should be analyzed as a contribution to the whole portfolio. Modern Portfolio Theory seeks to maximize expected return given an expected risk level or, equivalently, minimize expected risk given an expected return. Other forms of portfolio construction may legitimately pursue other objectives, such as optimizing for income, or minimizing loss of principal. Asset class selection Our approach to asset allocation starts with a universe of investable assets, which could be thought of as the “global market” portfolio.2 To capture the exposures of the asset classes for the global market portfolio, we evaluate available exchange-traded funds (ETFs) that represent each class in the theoretical market portfolio. We base our asset class selection on ETFs because this aligns portfolio construction with our fund selection methodology. All of our portfolios are constructed of the following asset classes: Stocks U.S. stocks International developed market stocks Emerging market stocks Bonds U.S. short-term treasury bonds U.S. inflation-protected bonds U.S. investment-grade bonds U.S. municipal bonds International developed market bonds Emerging market bonds We select U.S. and international developed market stocks as a core part of the portfolio. Historically, stocks exhibit a high degree of volatility, but provide some degree of inflation protection. Even though significant historical drawdowns, such as the global financial crisis in 2008 and pandemic outbreak in 2020, demonstrate the possible risk of investing in stocks, longer-term historical data and our forward expected returns calculations suggest that developed market stocks remain a core part of any asset allocation aimed at achieving positive returns. This is because, over the long term, developed market stocks have tended to outperform bonds on a risk-adjusted basis. To achieve a global market portfolio, we also include stocks from less developed economies, called emerging markets. Generally, emerging market stocks tend to be more volatile than U.S. and international developed stocks. And while our research shows high correlation between this asset class and developed market stocks, their inclusion on a risk-adjusted basis is important for global diversification. Note that we exclude frontier markets, which are even smaller than emerging markets, due to their widely-varying definition, extreme volatility, small contribution to global market capitalization, and cost to access. We incorporate bond exposure because, historically, bonds have a low correlation with stocks, and they remain an important way to dial down the overall risk of a portfolio. To promote diversification and leverage various risk and reward tradeoffs, we include exposure to several asset classes of bonds. All Betterment-constructed portfolios with the exception of the Flexible portfolio target a small operational cash allocation in taxable accounts, health savings accounts, and individual retirement accounts (IRAs). Asset classes excluded from Betterment portfolios While Modern Portfolio Theory would have us craft a portfolio to represent the total market, including all available asset classes, we exclude some asset classes whose cost and/or lack of data outweighs the potential benefit gained from their inclusion. Our portfolio construction process excludes commodities and natural resources asset classes. Specifically, while commodities represent an investable asset class in the global financial market, we have excluded commodities ETFs because of their low contribution to a global stock/bond portfolio's risk-adjusted return. In addition, real estate investment trusts (REITs), which tend to be well marketed as a separate asset class, are not explicitly included in our portfolios. We do provide exposure to real estate, but as a sector within stocks. Adding additional real estate exposure by including a REIT asset class would overweight the exposure to real estate relative to the overall market. Incorporating awareness of a benchmark Before 2024, we managed our portfolios in a “benchmark agnostic” manner, meaning we did not incorporate consideration of global stock and bond indices in our portfolio optimization, though we have always sought to optimize the expected risk-adjusted return of the portfolios we construct for clients. The “risk” element of this statement represents volatility and the related drawdown potential of the portfolio, but it could also represent the risk in the deviation of the portfolio’s performance relative to a benchmark. In an evolution of our investment process, in 2024 we updated our portfolio methodology to become “benchmark aware,” as we now calibrate our exposures based on a custom benchmark that expresses our preference for diversifying across global stocks and bonds. A benchmark, which comes in the form of a broad-based market index or a combination of indices, serves as a reference point when approaching asset allocation, understanding investment performance, and aligning the expectations of portfolio managers and clients. In our case, we created a custom benchmark that most closely aligns with our future expectations for global markets. The custom benchmark we have selected is composed of: The MSCI All Country World stock IMI index (MSCI ACWI IMI) The Bloomberg U.S. Universal Bond index The S&P US Treasury Bond 0-1 Year Index (for <40% stock allocations) Our custom benchmark is composed of 101 risk levels of varying percentage weightings of the stock and bond indexes, which correspond to the 101 risk level allocations in our Core portfolio. At low risk levels (allocations that are less than 40% stocks), we layer an allocation to the S&P US Treasury Bond 0-1 Year Index, which represents short-term bonds, into the blended benchmark. We believe that incorporating this custom benchmark into our process reinforces the discipline of carefully evaluating the ways in which our portfolios’ performance could veer from global market indices and deviate from our clients’ expectations. We have customized the benchmark with 101 risk levels so that it serves clients’ varying investment goals and risk tolerances. As we will explore in the following section, establishing a benchmark allows us to apply constraints to our portfolio optimization that ensures the portfolio’s asset allocation does not vary significantly from the geographic and market-capitalization size exposures of a sound benchmark. Our benchmark selection also makes explicit that the portfolio delivers global diversification rather than the more narrowly-concentrated and home-biased exposures of other possible benchmarks such as the S&P 500. III. Portfolio optimization As an asset manager, we fine-tune the investments our clients hold with us, seeking to maximize return potential for the appropriate amount of risk each client can tolerate. We base this effort on a foundation of established techniques in the industry and our own rigorous research and analysis. While most asset managers offer a limited set of model portfolios at a defined risk scale, our portfolios are designed to give customers more granularity and control over how much risk they want to take on. Instead of offering a conventional set of three portfolio choices—aggressive, moderate, and conservative—our portfolio optimization methods enable our Core portfolio strategy to be customized to 101 different stock-bond risk levels. Optimizing portfolios Modern Portfolio Theory requires estimating variables such as expected-returns, covariances, and volatilities to optimize for portfolios that sit along an efficient frontier. We refer to these variables as capital market assumptions (CMAs), and they provide quantitative inputs for our process to derive favorable asset class weights for the portfolio strategy. While we could use historical averages to estimate future returns, this is inherently unreliable because historical returns do not necessarily represent future expectations. A better way is to utilize the Capital Asset Pricing Model (CAPM) along with a utility function which allows us to optimize for the portfolio with a higher return for the risk that the investor is willing to accept. Computing forward-looking return inputs Under CAPM assumptions, the global market portfolio is the optimal portfolio. Since we know the weights of the global market portfolio and can reasonably estimate the covariance of those assets, we can recover the returns implied by the market.3 This relationship gives rise to the equation for reverse optimization: μ = λ Σ ωmarket Where μ is the return vector, λ is the risk aversion parameter, Σ is the covariance matrix, and ωmarket is the weights of the assets in the global market portfolio.5 By using CAPM, the expected return is essentially determined to be proportional to the asset’s contribution to the overall portfolio risk. It’s called a reverse optimization because the weights are taken as a given and this implies the returns that investors are expecting. While CAPM is an elegant theory, it does rely on a number of limiting assumptions: e.g., a one period model, a frictionless and efficient market, and the assumption that all investors are rational mean-variance optimizers.4 In order to complete the equation above and compute the expected returns using reverse optimization, we need the covariance matrix as an input. This matrix mathematically describes the relationships of every asset with each other as well as the volatility risk of the assets themselves. In another more recent evolution of our investment process, we also attempt to increase the robustness of our CMAs by averaging in the estimates of expected returns and volatilities published by large asset managers such as BlackRock, Vanguard, and State Street Global Advisors. We weight the contribution of their figures to our final estimates based on our judgment of the external provider’s methodology. Constrained optimization for stock-heavy portfolios After formulating our CMAs for each of the asset classes we favor for inclusion in our portfolio methodology, we then solve for target portfolio allocation weights (the specific set of asset classes and the relative distribution among those asset classes in which a portfolio will be invested) with the range of possible solutions constrained by limiting the deviation from the composition of the custom benchmark. To robustly estimate the weights that best balance risk and return, we first generate several thousand random samples of 15 years of expected returns for the selected asset classes based on our latest CMAs, assuming a multivariate normal distribution. For each sample of 15 years of simulated expected return data, we find a set of allocation weights subject to constraints that provide the best risk-return trade-off, expressed as the portfolio’s Sharpe ratio, i.e., the ratio of its return to its volatility. Averaging the allocation weights across the thousands of return samples gives a single set of allocation weights optimized to perform in the face of a wide range of market scenarios (a “target allocation”). The constraints are imposed to make the portfolio weights more benchmark-aware by setting maximum and minimum limits to some asset class weights. These constraints reflect our judgment of how far the composition of geographic regions within the portfolio’s stock and bond allocations should differ from the breakdown of the indices used in the benchmark before the risk of significantly varied performance between the portfolio strategy and the benchmark becomes untenable. For example, the share of the portfolio’s stock allocation assigned to international developed stocks should not be profoundly different from the share of international developed stocks within the MSCI ACWI IMI. We implement caps on the weights of emerging market stocks and bonds, which are often projected to have high returns in our CMAs, and set minimum thresholds for U.S. stocks and bonds. This approach not only ensures our portfolio aligns more closely with the benchmark, but it also mitigates the risk of disproportionately allocating to certain high expected return asset classes. Constrained optimization for bond-heavy portfolios For Betterment portfolios that have more than or equal to a 60% allocation of bonds, the optimization approach differs in that expected returns are maximized for target volatilities assigned to each risk level. These volatility targets are determined by considering the volatility of the equivalent benchmark. Manually established constraints are designed to manage risk relative to the benchmark, instituting a declining trend in emerging market stock and bond exposures as stock allocations (i.e., the risk level) decreases. Meaning that investors with more conservative risk tolerances have reduced exposures to emerging market stocks and bonds because emerging markets tend to have more volatility and downside-risk relative to more established markets. Additionally, as the stock allocation percentage decreases, we taper the share of international and U.S. aggregate bonds within the overall bond allocation, and increase the share of short-term Treasury, short-term investment grade, and inflation-protected bonds. This reflects our view that investors with more conservative risk tolerances should have increased exposure to short-term Treasury, short-term investment grade, and inflation-protected bonds relative to riskier areas of fixed income. The lower available risk levels of our portfolios demonstrate capital preservation objectives, as the shorter-term fixed income exposures likely possess less credit and duration risk. Clients invested in the Core portfolio at conservative allocation levels will likely therefore not experience as significant drawdowns in the event of waves of defaults or upward swings in interest rates. Inflation-protected securities also help buffer the lower risk levels from upward drafts in inflation. IV. Tax management using municipal bonds For investors with taxable accounts, portfolio returns may be further improved on an after-tax basis by utilizing municipal bonds. This is because the interest from municipal bonds is exempt from federal income tax. To take advantage of this, we incorporate municipal bonds within the bond allocations of taxable accounts. Other types of bonds remain for diversification reasons, but the overall bond tax profile is improved by incorporating municipal bonds. For investors in states with some of the highest tax rates—New York and California—Betterment can optionally replace the municipal bond allocation with a more narrow set of bonds for that specific state, further saving the investor on state taxes. Betterment customers who live in NY or CA can contact customer support to take advantage of state-specific municipal bonds. V. The Value Tilt portfolio strategy Existing Betterment customers may recall that historically the Core portfolio held a tilt to value companies, or businesses that appear to be potentially undervalued based on metrics such as price-to-earnings (P/E) ratios. Recent updates, however, have deprecated this explicit tilt that was expressed via large-, mid-, and small-capitalization U.S. value stock ETFs, while maintaining some exposure to value companies through broad market U.S. stock funds. We no longer favor allocating to value stock ETFs within our portfolio methodology in large part as a result of our adoption of a broad market benchmark, which highlights the idiosyncratic nature of such tilts, sometimes referred to as “off benchmark bets.” We believe our chosen benchmark that represents stocks through the MSCI ACWI IMI, which holds a more neutral weighting to value stocks, more closely aligns with the risk and return expectations of Betterment’s diverse range of client types across individuals, financial advisors, and 401(k) plan sponsors. Additionally, as markets have grown more efficient and value factor investing more popularized, potentially compressing the value premium, we have a marginally less favorable view of the forward-looking, risk-adjusted return profile of the exposure. That being said, we have not entirely lost conviction in the research supporting the prudence of value investing. The value factor’s deep academic roots drove decisions to incorporate the value tilt into Betterment’s portfolios from our company’s earliest days. For investors who wish to remain invested in a value strategy, we have added the Value Tilt portfolio, a separate option from the Core portfolio, to our investing offering. The Value Tilt portfolio maintains the Core portfolio’s global diversification across stocks and bonds while including a sleeve within the stock allocation of large-, mid-, and small-capitalization U.S. value funds. We calibrated the size of the value fund exposure based on a certain target historical tracking error to the backtested performance of the latest version of the Core portfolio. Based on this approach, investors should expect the Value Tilt portfolio to generally perform similarly to Core, with the potential to under- or outperform based on the return of U.S. value stocks. With the option to select between the Value Tilt portfolio or a Core portfolio now without an explicit allocation to value, the investment flexibility of the Betterment platform has improved. VI. The Innovative Technology portfolio strategy In 2021, Betterment launched the Innovative Technology portfolio to provide access to the thematic trend of technological innovation. The portfolio’s investment premise is based upon the thesis that, over the long term, the companies innovating and disrupting their respective industries are shaping our global economy and may be the winners of the next industrial revolution. Some of these themes the portfolio seeks to provide increased exposure to are: Artificial intelligence Alternative finance Clean energy Manufacturing Biotechnology Similar to the Value Tilt portfolio, the Core portfolio is used as the foundation of construction for the Innovative Technology portfolio. With this portfolio strategy, we calibrated the size of the innovative technology funds’ exposure based on a certain target historical tracking error to the backtested performance of the latest version of the Core portfolio. Through this process, the Innovative Technology portfolio maintains the same globally-diversified, low-cost approach that is found in Betterment’s investment philosophy. The portfolio, however, has increased exposure to risk given that innovation requires a long-term view, and may face uncertainties along the way. It may outperform or underperform depending on the return experience of the innovative technology funds’ exposure and the thematic landscape. To learn more, read the Innovative Technology portfolio disclosure. VII. The Socially Responsible Investing portfolio strategies Betterment introduced its first Socially Responsible Investing (SRI) portfolio in 2017 and has since expanded the options to include three distinct portfolios: Broad Impact, Social Impact, and Climate Impact. These SRI portfolios are built on the same foundational principles as the Core portfolio, utilizing various asset classes to create globally-diversified portfolios. However, they incorporate socially-responsible ETFs that align with specific Environmental, Social, and Governance (ESG) and shareholder engagement mandates, tailored to each SRI focus. Betterment’s SRI approach emphasizes three core dimensions: Reducing exposure to companies engaged in unsustainable activities Increasing investments in those addressing environmental and social challenges Allocating to funds that utilize shareholder engagement to promote responsible corporate behavior. This methodology ensures diversified, cost-efficient portfolios that resonate with investors' values. For more information, read our full Socially Responsible Investing portfolios methodology. VIII. Conclusion After setting the strategic weight of assets in our various Betterment portfolios, the next step in implementing the portfolio construction process is our fund selection methodology, which selects the appropriate ETFs for the respective asset exposure in a generally low-cost, tax-efficient way. In keeping with our philosophy, that process, like our portfolio construction process, is executed in a systematic, rules-based way, taking into account the cost of the fund and the liquidity of the fund. Beyond ticker selection is our established process for allocation management—how we advise downgrading risk over time. The level of granularity in allocation management provides the flexibility to align to multiple goals with different timelines and circumstances. Most of our portfolios contain 101 individualized risk levels (each with a different percentage of the portfolio invested in stocks vs. bonds, informed by your financial goals, time horizon and risk tolerance). Finally, our overlay features of automated rebalancing, tax-loss harvesting, and our methodology for automatic asset location, which we call Tax Coordination, are designed to be used to help further maximize individualized, after-tax returns. Together these processes put our principles into action, to help each and every Betterment customer maximize value while invested at Betterment and when they take their money home. IX. Citations 1 Markowitz, H., "Portfolio Selection".The Journal of Finance, Vol. 7, No. 1. (Mar., 1952), pp. 77-91. 2 Black F. and Litterman R., Asset Allocation Combining Investor Views with Market Equilibrium, Journal of Fixed Income, Vol. 1, No. 2. (Sep., 1991), pp. 7-18. Black F. and Litterman R., Global Portfolio Optimization, Financial Analysts Journal, Vol. 48, No. 5 (Sep. - Oct., 1992), pp. 28-43. 3 Litterman, B. (2004) Modern Investment Management: An Equilibrium Approach. 4 Note that the risk aversion parameter is essentially a free parameter. 5 Ilmnen, A., Expected Returns.