6 min read · Last updated September 22, 2026
- Vanguard’s Target Retirement 2060 Fund (VTTSX) charges 0.08% a year, about $40 annually on a $50,000 balance; a self-built three-fund portfolio using Vanguard’s own index funds can run as low as 0.04%, about $20 a year on the same balance.
- Betterment and Wealthfront both charge a flat 0.25% annual advisory fee, about $125 a year on $50,000, and both include automatic tax-loss harvesting; Schwab Intelligent Portfolios currently charges $0 in advisory fees.
- Tax-loss harvesting only has value inside a taxable brokerage account. Trades inside a 401(k) or an individual retirement account (IRA) aren’t taxed every year, so a robo-advisor’s signature feature does nothing there.
- The real cost gap between a target-date fund and a do-it-yourself three-fund portfolio is small enough that the decision should hinge on whether you’ll actually rebalance yourself, not on the fee.
A target-date fund and a self-built three-fund portfolio cost within about $20 of each other every year on a $50,000 balance, but a robo-advisor’s 0.25% fee, roughly $125 a year on the same balance, only pays for itself through automatic tax-loss harvesting inside a taxable account, since that feature does nothing inside a 401(k) or an IRA.
In this article
- What each option actually is
- The real cost, side by side
- Why the robo-advisor’s fee isn’t really about the funds
- Tax-loss harvesting only works in one kind of account
- Frequently asked questions
Three ways exist to hold a diversified investment portfolio without picking individual stocks: a single target-date fund, a self-built three-fund portfolio, or a robo-advisor – and the cheapest-looking option on paper isn’t always the cheapest in practice. Vanguard’s Target Retirement 2060 Fund (VTTSX) charges 0.08% a year, or about $40 annually on a $50,000 balance. A self-built three-fund portfolio using Vanguard’s own index funds can run as low as 0.04%, about $20 a year on the same balance. A robo-advisor like Betterment or Wealthfront charges a flat 0.25% fee, about $125 a year on $50,000 – three to six times more than the other two options. The deciding question isn’t which one is cheapest. It’s which account the money sits in, and whether you’ll actually do the rebalancing yourself.
What each option actually is
A target-date fund is one fund that holds a mix of stocks and bonds and automatically shifts that mix to be more conservative as you approach the year in its name. You buy it once and never touch it again; the fund company does the rebalancing.
A three-fund portfolio is the do-it-yourself (DIY) version: you buy a U.S. total stock market index fund, an international stock index fund, and a total bond market index fund separately, and you decide the split yourself. Nothing rebalances automatically – if stocks run up and your allocation drifts from your target, you have to sell some and buy more of the others yourself, typically once a year.
A robo-advisor is a managed account: you answer a few questions about your goals and risk tolerance, and the platform builds and automatically rebalances a portfolio of funds for you, for an annual fee on top of what those underlying funds already cost.
The real cost, side by side
| Factor | Target-Date Fund | Three-Fund Portfolio | Robo-Advisor |
|---|---|---|---|
| Typical annual cost on $50,000 | About $40 (0.08%, VTTSX) | About $20-$45 depending on your split (0.04%-0.09% per fund) | About $125 (0.25%, Betterment or Wealthfront) |
| Who rebalances | Automatic, built into the fund | You, manually, usually once a year | Automatic |
| Tax-loss harvesting included | Not offered | Not offered – you’d have to do it yourself | Automatic, included in the advisory fee |
| Ongoing effort required | Buy once, do nothing else | Choose your split, then rebalance it yourself over time | Buy once, do nothing else |
| Best for | Investors who want one fund and zero ongoing decisions | Cost-conscious investors who will actually manage it themselves | Taxable-account investors who want harvesting automated and don’t mind paying more for it |
Run the arithmetic on a $50,000 balance and the target-date fund and the cheapest realistic three-fund split land within about $20 of each other every year. The robo-advisor is the real outlier – about $105 more a year than the cheapest three-fund split, and about $85 more than the target-date fund.
Why the robo-advisor’s fee isn’t really about the funds
A robo-advisor’s 0.25% fee doesn’t cover better underlying investments – Betterment and Wealthfront both build their portfolios out of ordinary index-fund-style exchange-traded funds (ETFs), not something exotic. What the fee actually buys is automatic rebalancing (which a target-date fund also gives you for a fraction of the price) plus automatic tax-loss harvesting, which neither the target-date fund nor the DIY portfolio offers at all. If you’d never do the harvesting yourself and it’s sitting in the right kind of account, that’s a real, paid-for feature. If it’s sitting in the wrong kind of account, you’re paying for nothing.
Not every robo-advisor charges the same amount. Schwab Intelligent Portfolios currently publishes a $0 advisory fee – Schwab says it earns its money instead from the cash allocation built into every portfolio. Before ruling out a robo-advisor on cost alone, check what a specific provider actually charges; the fee line varies more between robo-advisors than it does between a target-date fund and a DIY three-fund split.
Tax-loss harvesting only works in one kind of account
This is the detail that decides the whole comparison for a lot of readers. Tax-loss harvesting works by selling an investment that’s lost value to realize a deductible loss, then replacing it with something similar so the money stays invested. That only matters where investment gains and losses are taxed every year – a taxable brokerage account. A traditional or Roth IRA isn’t taxed that way: contributions and qualified withdrawals are what trigger tax consequences, not the trades happening inside the account. Selling a losing fund inside a 401(k) or an IRA to “harvest a loss” accomplishes nothing, because there was never an annual tax bill on those trades to offset in the first place.
That means the same robo-advisor fee that can genuinely pay for itself in a taxable brokerage account is pure cost with zero offsetting benefit inside a 401(k) or an IRA – you’d be paying 0.25% a year for a feature that literally cannot activate.
Choose the option that matches your account and your habits
Choose the target-date fund if the money is inside a 401(k) or an IRA, you want to buy one thing and never think about it again, and the small cost gap versus a DIY portfolio doesn’t bother you.
Choose the three-fund portfolio if you want the lowest possible cost and you’re honest with yourself that you’ll actually rebalance it – realistically, checking it once a year and nudging the percentages back toward your target.
Choose a robo-advisor if the money is in a taxable brokerage account where tax-loss harvesting’s savings can plausibly exceed the fee, or you want automatic rebalancing and tax management handled together without doing either yourself.
What could change the calculus
Fees on all three change over time, so recheck the current numbers before you commit real money. And the account type matters more than any other single factor here: the same robo-advisor that’s a smart pick for a taxable account is close to the worst value on this list for a tax-advantaged one, because you’d be paying full price for a feature that can’t do anything there.
Frequently asked questions
Is a target-date fund automatically rebalanced? Yes. The fund manager continuously adjusts the mix of stocks and bonds inside the single fund as the target year approaches, and shifts the whole portfolio more conservative over time. You never place a trade yourself.
Can I do tax-loss harvesting on my own instead of paying a robo-advisor for it? Yes, but it takes ongoing attention: monitoring your taxable holdings for losses, selling at the right time, and buying a similar-but-not-identical replacement to avoid the Internal Revenue Service’s wash-sale rule. A robo-advisor automates that work for its 0.25% fee.
Does a robo-advisor’s tax-loss harvesting matter inside a Roth IRA? No. A Roth IRA isn’t subject to annual capital-gains tax on trades made inside it, so there’s no yearly tax bill for harvesting to offset. Paying an advisory fee for tax-loss harvesting inside a Roth IRA buys a feature that has nothing to do.
What’s the cheapest way to build a three-fund portfolio? Buying Vanguard’s own Admiral share index funds directly (or the ETF equivalents) keeps the cost at each fund’s published expense ratio, with no advisory layer added on top. The trade-off is that you’re responsible for choosing the split and rebalancing it yourself.
Is Schwab Intelligent Portfolios really free? Schwab currently charges no advisory fee, but you still pay the operating expenses built into the underlying ETFs the portfolio holds, the same way you would with any fund. “Free” refers to the advisory layer, not every cost in the account.
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