To see what a micro-investing app’s flat monthly fee costs you, multiply it by 12 and divide by your balance. On a small balance, that yearly percentage can be close to or above the 10% a year large U.S. stocks have averaged since 1928. Until it falls under 1%, invest through a broker with no account fee.
Acorns charges $4, $8, or $12 a month, depending on the plan, and Stash’s plan costs $12 a month, or $108 for a year paid up front. Those prices stay the same whatever your balance, so they take the biggest percentage of a small one.
At $4 a month, you pay $48 a year, which is 9.6% of a $500 balance. That 9.6% is nearly all of the 10% a year the S&P 500, an index of 500 large U.S. companies, has returned on average since 1928, according to data from NYU professor Aswath Damodaran.
Index stock mutual funds, which track an index like the S&P 500, charged an average fee of 0.05% a year in 2025, the Investment Company Institute found. On the same $500, that’s 25 cents a year against the app’s $48.
When you do the math, count every balance the fee covers, the app’s retirement account included, not just its regular investing account. A $12 monthly fee on $2,000 across both is $144 a year, or 7.2%.
Round-ups, which invest the spare change from each purchase, can be worth the fee while they’re the only way you’d invest at all. You can build the same habit for free, though. Check what your round-ups added last month, then set up an automatic monthly investment of that amount at an online broker with no account fee. Pick one that sells fractional shares, so even $20 buys a slice of a fund that tracks the S&P 500.
The fee drops below 1% a year, a tenth of the S&P 500’s 10% average, once your balance reaches 1,200 times the monthly fee. That’s a balance of $4,800 on a $4 plan and $14,400 on a $12 plan.
To set up that automatic investment, compare the best online brokers.
Editorial & Advertiser Disclosure: The editorial content on this page is not provided, commissioned, reviewed, approved, or otherwise endorsed by any advertiser. Opinions expressed here are ours alone, not those of any advertiser. The offers that appear on this site are from companies that compensate us. That compensation may influence which products we cover and where and how they appear on a page – including the order in which they appear – but it does not influence our evaluations, ratings, or opinions. We do not include every company or offer available in the marketplace.
Related:
