Acorns vs SigFig: Which Is Better in 2026?

Figures and features are point-in-time and change; treat the table as a starting map, not a live quote.

Round-ups and small automated contributions into a diversified ETF portfolio, priced as a monthly subscription rather than a percentage.

How it works: Acorns rounds up card purchases to the nearest dollar and invests the difference, alongside optional recurring contributions, into a diversified ETF portfolio chosen by questionnaire. Pricing is a flat monthly fee by tier rather than a percentage of assets, which inverts the usual arithmetic.

In practice, Acorns’s AI automates small recurring investments. It falls under hands-off automated investing (robo-advisors), which makes it best suited to starting to invest at all, when the barrier is behavioural. On connecting an account it is “No (holds your money at Acorns)”, and on execution it is “Automated”. It is priced as flat monthly subscription tiers (verify current).

One honest limitation: A flat monthly fee is enormous as a percentage of a small balance, which is exactly the balance the product is designed for.

An automated investing service that manages accounts held at your existing broker rather than requiring you to move money.

How it works: Rather than opening a new account, you link an existing brokerage account at a supported custodian and SigFig manages it in place, rebalancing and running tax-efficient strategies. Below a stated balance the management is free. This structure is unusual: nearly every competitor requires custody of your assets.

In practice, SigFig’s AI automates a portfolio in accounts you already hold. It falls under hands-off automated investing (robo-advisors), which makes it best suited to automation that manages your existing schwab or fidelity account. On connecting an account it is “Yes, it manages accounts held at supported brokers”, and on execution it is “Automated”. It is priced as free under a stated balance, then a percentage (verify current).

One honest limitation: Supported custodians are limited, so it only works if your account is already at one of them.

The core difference is category. Acorns focuses on starting to invest at all, when the barrier is behavioural (automates small recurring investments), and SigFig on automation that manages your existing schwab or fidelity account (automates a portfolio in accounts you already hold). On broker connection they differ too: Acorns is “No (holds your money at Acorns)” versus SigFig at “Yes, it manages accounts held at supported brokers”. That shapes everything downstream: how personal the answers are, where trades settle, and how much control you keep over individual positions.

Every tool gives something up for what it does well. Here is the honest give-and-take on each, so you can weigh the specific strengths against the limitations that come with them rather than judging on the headline category alone.

For AI investing tools, the distinction that matters most is whether the tool works from your actual, connected positions or reasons from something else: a separate account it manages for you, or the tickers and numbers you feed it. It decides how personal the answers can be, and where your money physically lives.

• Acorns: manages a separate account it holds. Acorns does not read the brokerage you already use. It opens and holds a new account, then invests the money you move into it, so its view is limited to what sits inside Acorns.
• SigFig: manages a separate account it holds. SigFig does not read the brokerage you already use. It opens and holds a new account, then invests the money you move into it, so its view is limited to what sits inside SigFig.

On this specific question the two land on the same side, so the deciding factors between them are elsewhere: category, cost, and who each is built for. This holdings-aware angle is the one Walnut is built around: it connects the brokerage you already use and reasons from your live positions, read-only by default, with any trades left for you to approve.

There is no universal winner here; the right pick depends on the job you are hiring the tool for. Match the category to your intent rather than chasing a single “best.”

• Choose Acorns if you want starting to invest at all, when the barrier is behavioural. Its AI automates small recurring investments, it is priced as flat monthly subscription tiers (verify current), and it fits hands-off automated investing (robo-advisors). It is built for someone who has not managed to start investing and needs the decision removed, with a plan to reassess the fee once the balance grows. Keep in mind that a flat monthly fee is enormous as a percentage of a small balance, which is exactly the balance the product is designed for.
• Choose SigFig if you want automation that manages your existing schwab or fidelity account. Its AI automates a portfolio in accounts you already hold, it is priced as free under a stated balance, then a percentage (verify current), and it fits hands-off automated investing (robo-advisors). It is built for someone with an existing account at a supported broker who wants it managed without moving anything. Keep in mind that supported custodians are limited, so it only works if your account is already at one of them.

Because both sit in the same category, the choice comes down to the finer details above rather than a fundamental difference in approach.

Cost is easy to misread when two tools charge in different shapes, so compare the model, not just the number. Acorns is priced as flat monthly subscription tiers (verify current), while SigFig is priced as free under a stated balance, then a percentage (verify current). A percentage-of-assets fee scales with your balance, a flat subscription does not, and a “free” tier usually earns elsewhere (on cash, order flow, or premium upgrades), so the cheapest headline is not always the cheapest outcome for your situation.

Pricing and tiers change often. Confirm the current numbers on each provider’s own site before you decide; the framing above is point-in-time.

If neither quite fits, Walnut sits in a third category: chat-driven management of your own brokerage. It connects the brokerage you already use through SnapTrade, lets you analyze and manage it by talking through Claude or ChatGPT, build thematic portfolios around a thesis, and place trades you approve. Read-only by default. See Walnut vs Acorns and Walnut vs SigFig. Walnut is not an investment adviser.