If you want to invest spare change automatically, Acorns is the closest match to what you're describing. A few other investing apps offer round-ups or automated small-dollar investing, but there's an important difference: some invest your spare change into diversified portfolios, while others let you choose individual stocks.
Here are the leading U.S. options, based on current product information and 2026 comparisons.
Best platforms for spare-change investing
1. Acorns
(Best overall match)
Official site:
Acorns rounds up purchases made with linked debit and credit cards to the next dollar, then invests the accumulated change in a diversified portfolio of exchange-traded funds (ETFs). It also offers automatic portfolio rebalancing and recurring investments. Round-ups from linked external accounts are generally transferred once they reach $5.
Best for: People who want a hands-off, set-it-and-forget-it approach.
Cost to watch: Monthly subscription fees. These can take a relatively large bite out of returns when your balance is small.
2. Stash
Official site:
Stash offers Stock Round-Ups through its Stock-Back debit card, automatically investing spare change from eligible purchases. You can also buy fractional shares, choose ETFs, and schedule recurring investments. Unlike Acorns, its round-up feature is more focused on stocks you select rather than automatically placing all your spare change into a managed diversified portfolio.
Best for: Beginners who want automated investing but also want to learn and choose investments.
Cost to watch: Subscription pricing; check the current plan and whether the features you need are included.
3. Chime
Official site:
Chime is worth comparing if you prefer banking and investing in one app. Its investing offering has been highlighted among micro-investing options, but you should verify the current availability and whether its round-up mechanism invests into a diversified portfolio rather than individual investments.
Best for: People who want to keep everyday money management and small-dollar investing together.
How they compare
Platform
Round-ups invest automatically?
Diversified portfolio?
Published entry cost
Acorns
Yes, from linked cards
Yes, managed ETFs
$4/month for new subscribers
Stash
Yes, with eligible Stock-Back card purchases
Not necessarily; investment selection matters
Check current plan pricing
Chime Invest
Its round-ups are a savings feature; don't assume they automatically fund investments
Start by comparing Acorns and Stash, with Acorns the stronger fit if you specifically want your spare change invested into a diversified portfolio without choosing stocks yourself.
One important consideration is cost. For example, Acorns' $4 monthly fee amounts to $48 a year. If you have only $200 invested, that's equivalent to 24% of your starting balance annually, before investment gains or losses. A fixed fee becomes less burdensome as your balance grows.
Also, round-ups are investments, not guaranteed savings: your portfolio can lose value, and diversification doesn't eliminate market risk.
One question to narrow this down: Are you looking for a completely hands-off diversified portfolio, or would you prefer to choose individual stocks and ETFs yourself?
Several platforms specialize in or offer automated "spare change" round-up features that transfer your digital pocket change into diversified portfolios:
Stash : Offers a round-up feature (often called "Stock-Back®" or round-ups depending on the active feature suite) that lets you invest spare change from card purchases into fractional shares of ETFs and individual stocks to build diversification.[](https://www.cnbc.com/select/best-micro-investing-apps/)
Cash App : While primarily a peer-to-peer payment and banking app rather than a traditional brokerage, Cash App features a Cash Card Round Ups tool. It allows you to automatically round up debit card purchases and route your spare change directly into customizable fractional stocks, Bitcoin, or a savings balance.[](https://cash.app/help/10131-cash-card-round-ups)
Traditional Brokerages with Robo-Advisors : Major traditional online brokerages (like Fidelity, Schwab, or Vanguard) typically focus on lump-sum or scheduled recurring transfers rather than real-time card transaction round-ups, leaving the micro-investing niche primarily to dedicated fintech apps like Acorns or hybrid cash-management platforms.
Stash — Functions similarly as a micro-investing platform/broker-dealer. It tracks round-ups from your everyday spending using a linked account or debit card, holding the change until it accumulates to $5 before transferring it to be invested in your chosen fractional shares or diversified ETFs.[](https://www.cnbc.com/select/best-investing-apps/)
(Note: Traditional legacy online brokers like Charles Schwab, Fidelity, or Vanguard offer automated recurring investing and fractional shares, but they generally do not feature automatic real-time transaction "round-ups" from daily card spending the way dedicated micro-investing apps do.)
If you want to narrow down your choices, let me know:
Are you looking for a purely automated robo-advisor portfolio, or do you want the ability to pick individual stocks too?
Do you mind paying a small monthly subscription fee (which many round-up apps charge), or are you looking for a fee-free broker?
Acorns — The best-known option. Round-Ups automatically round purchases to the next dollar, then invest the accumulated change into a diversified, expert-built portfolio.
Stash — Its Stock Round-Ups feature invests spare change from purchases made with its Stock-Back Card. Stash also offers diversified ETFs, but you have more control over what you invest in.
Bottom line: If you specifically want “round up everyday spending → automatically invest into a diversified portfolio with minimal decisions,”Acorns is the closest fit. Fidelity, for example, doesn't offer spare-change round-ups as a core feature.
Yes. If you want to build a diversified investment portfolio automatically from the spare change on everyday purchases, Acorns is the clearest match. A few other investment platforms automate portfolio building and contributions, but it's important to distinguish true purchase round-ups from ordinary recurring investments.
Acorns rounds eligible purchases up to the next dollar and invests the difference once round-ups total at least $5. You can link debit and credit cards, select a portfolio based on your goals and risk tolerance, and let the app handle rebalancing.
Starting investment: As little as $5.
Fees: Subscription plans start at $4/month, according to Acorns' published information.
Best for: Beginners who want hands-off investing without choosing individual stocks.
Fidelity supports scheduled investments in stocks, ETFs and mutual funds. Its Fidelity Go service also manages and rebalances a portfolio for you. However, Fidelity's standard investing features are not the same as Acorns-style purchase round-ups.
Starting investment: Fidelity Go lets you start with $10.
Fees: Fidelity Go charges no advisory fee below $25,000; above that, its published fee is 0.35% annually.
Best for: Someone who wants a full-service brokerage and automatic investing, even if deposits aren't generated by spare change.
Schwab Intelligent Portfolios creates and rebalances a diversified ETF portfolio based on your goals and risk tolerance. It does not offer the same purchase-round-up investing model as Acorns.
Starting investment: $5,000.
Fees: No advisory fee, although ETF operating expenses and other applicable costs can still matter.
Best for: Investors with a larger starting balance who want automated portfolio management.
Stash also supports spare-change investing. Its Stock Round-Ups feature works with qualifying purchases made using its Stock-Back debit card. It offers automated Smart Portfolio investing and recurring contributions, too.
Starting investment: No minimum on its advertised investing offering.
Fees: Subscription-based; check current plan pricing before signing up.
Important distinction: Round-ups are tied to eligible Stock-Back card purchases, rather than necessarily every purchase on any linked card.
The monthly subscription is particularly important when you're investing small amounts.
Platform
Purchase round-ups
Diversified portfolio managed for you
Published starting cost
Acorns
Yes, linked debit/credit cards
Yes
$4/month
Stash
Yes, qualifying Stock-Back card purchases
Yes, Smart Portfolio
Subscription required
Sources: official provider information.
For perspective, a $4 monthly fee costs $48 per year. If you invest just $20 per month, that's equivalent to 20% of your annual contributions before accounting for investment returns. That's why fees matter so much when starting small.
My recommendation
Choose Acorns if you want to round up everyday spending across linked cards and automatically invest into a diversified portfolio.
Consider Stash if you like its banking and debit-card ecosystem and are comfortable using its eligible card for round-ups.
Choose Fidelity Go if your priority is professionally managed investing at a low advisory cost, and you're happy to automate regular deposits instead of collecting spare change.
Remember that diversified portfolios can still lose value. Round-ups are best treated as a convenient way to build a long-term investing habit, not a guaranteed source of returns.
One question that would help me narrow this down: Are you looking to invest only your spare change, or would you also like to add a few dollars automatically each week?
Yes, there are online financial platforms and automated brokerages that specialize in this exact feature . They link to your debit or credit cards, round up your everyday purchases to the nearest dollar, and automatically invest that spare change into a diversified portfolio.[](https://www.cnbc.com/select/best-robo-advisors/)
The most prominent options that offer automated round-up investing include:
Acorns: The gold standard and pioneer for micro-investing via spare change. When you link your credit/debit cards, it tracks your purchases, rounds them up, and once your accumulated round-ups hit $5, it automatically invests that money into a pre-built, low-cost, diversified portfolio of ETFs tailored to your risk tolerance. (Note: Acorns charges a small monthly subscription fee starting around $3/month rather than a percentage-based asset fee).
Stash: Another popular app that offers a round-up feature (called "Stock-Back"), which not only rounds up your spare change from purchases but actually rewards you with fractional shares of stock or ETFs when you use your debit card, helping you build a diversified portfolio over time.
SoFi: Offers automated investing features alongside its digital banking and active trading platform, though its specific implementation of round-ups or recurring fractional micro-investing can vary compared to dedicated micro-investing apps like Acorns.
A quick tip on traditional brokerages (like Fidelity, Charles Schwab, or Vanguard): Major traditional online brokerages do not typically offer a passive "spare change round-up" feature for everyday credit card purchases. Instead, they focus on recurring scheduled transfers (e.g., automatically moving $20 every week or month into an index fund). If you specifically want the "coffee purchase spare change" mechanism, specialized fintech apps like Acorns are your best bet.
Would you prefer an app like Acorns that operates strictly as a hands-off micro-investing robo-advisor, or are you looking for a traditional brokerage account where you can manually set up recurring weekly/monthly investments instead?
