Can a portfolio be too simple?

Can a portfolio be too simple? Dec 10, 2025 2:22:50 PM Total market funds offer simplicity, but by unbundling asset classes—and adding Betterment’s automation—you can make your money work harder. Key takeaways Single-fund portfolios are easy to build, but they’re harder to optimize for taxes and costs. Using multiple funds adds the flexibility to fine-tune allocations and unlock savings. Betterment’s automation and expert-built portfolios give you the best of both worlds: easy to invest in, and built to work harder. If you’re looking to build long-term wealth, you could do worse than investing in one or two low-cost, globally-diversified total market funds. But you could potentially do better—and spend less of your limited bandwidth—by using a few more pieces and putting our technology to work in your favor. That’s the value of Betterment’s automated investing and expert-built portfolios, and it begins with (surprise!) tax optimization. Harvesting losses for tax wins, and putting your assets in the right place Targeting more than a date Splitting hairs on fund fees, so customers can save millions Harvesting losses for tax wins, and putting your assets in the right place Tax-loss harvesting can help give your taxable investing an edge, and it happens when you sell an asset for a loss and replace it with a similar one. The downside of a total market fund, however, is you have to wait for the entire fund to experience a loss. If only one piece of it dips, you can’t unbundle the assets and harvest that specific piece. It’s sell all, or sell nothing. That’s a big reason why we switched from using a single fund for U.S. stocks in our Betterment-built portfolios, opting instead for three separate funds representing small, medium, and large-sized U.S. companies. If one of them presents a harvesting opportunity, we can swap it for a similar alternative. The second area where larger fund lineups shine is asset location, or strategically divvying up your portfolio’s assets among traditional, Roth, and/or taxable accounts. Stocks with the highest potential for growth, for example, are often better-suited for traditional accounts. Let them grow tax-free, the thinking goes, then settle up with Uncle Sam when you’re retired and more likely to be in a lower tax bracket. Our mathematically-rigorous spin on asset location is called Tax Coordination, and it’s yet another way our automated investing helps you keep more of what you earn. To start taking advantage of it, simply open any combination of the three account types above and follow a few easy steps. Start remixing your assets for potential tax savings. Targeting more than a date One of the most common single-fund options for retirement savings are target date funds. They date back to the 90s and became the default option in many 401(k) plans starting in the late 2000s. The growth of target date funds has been a good thing for investors, helping move the industry toward lower-cost, automated investing. Prior to their arrival, advisors had to manually adjust the asset allocations or “glide paths” of portfolios over time. Similar to total market funds, however, the bundling of target date funds brings with it some constraints. The first constraint is their relative lack of choice. Say you were born in 1988 and are targeting a traditional retirement age of 62. Most target date fund managers give you one option—the 2050 fund. Our automated investing, on the other hand, gives you more than a handful of portfolios to choose from, including ones tailored for social responsibility and innovation. More funds also creates more levers to fine-tune your exposure, helping manage risk in all sorts of situations. Take bond-heavy portfolios as an example. Rising interest rates can erode their value, so we dial up their exposure to short-term corporate debt and U.S. Treasuries specifically to help hedge against that risk. Splitting hairs on fund fees, so customers can save millions The relatively high cost of target date funds has been trending downward, and many total market funds can be found for expense ratios of less than 0.1%. But we can squeeze out even more savings by splitting a portfolio up and shopping for better deals. A single one hundredth of a percentage point in fund fees (what’s referred to as a “basis point” or “bip” in investing lingo) may not sound like much, but we owe it to our customers to make every one count. You could pay 6 basis points (0.06%), for example, for a total world stock fund like VT. Or you could pay one-third of that for your U.S. stock allocation by breaking it up into three funds (SPYM, SPMD, and SPSM) like we do with our Core portfolio and others. Using our customers’ nearly $20 billion worth of U.S. stocks as an example, that would amount to roughly $7.6 million in combined savings each year. Flexibility to stretch your investing dollars even farther A simple portfolio can be a great place to start, but it’s not always where your money works hardest. By strategically using a few more funds, we can sprinkle tax advantages on more of your investing, optimize across account types, and potentially unlock even more cost savings. All automatically. You get the simplicity you want, but with our tech doing the heavy lifting behind the scenes.