A penny test in banking is a verification step where a bank, payroll system, or payment app sends one or two tiny deposits, each less than a dollar, into your account and asks you to type back the exact amounts. If you can report the numbers correctly, the platform accepts that as proof you actually have access to the account. You’ll see it most often the first time you link a bank account to a payroll provider, brokerage, or payment service.
How the Deposits and Confirmation Work
After you submit your routing and account numbers, the platform sends two small credits through the ACH network. They show up in your transaction history as deposits of a few cents each. Some platforms also post a matching withdrawal so the net change to your balance is zero.
You then log back in and enter the two amounts exactly as they appear on your statement. Match them, and the account is verified. The reason this step exists at all is that ACH transactions move on routing and account numbers alone and have no built-in way to confirm who owns the receiving account. Nacha, which governs the ACH network, treats micro-deposit verification as a valid way to confirm an account is legitimate and active before pulling money from it.1Nacha. Supplementing Fraud Detection Standards for WEB Debits
The penny test also catches typos before they cause real damage. Transpose two digits in your account number and the deposits bounce or land somewhere else entirely. Better to lose a few cents than a paycheck.
What You Need to Start One
Three pieces of information get a penny test moving, and any one of them wrong stops the process:
- Your nine-digit routing number, printed along the bottom-left of a paper check or shown in your bank’s app under account details.2eCFR. Appendix A to Part 229 – Routing Number Guide
- Your account number, which sits to the right of the routing number on a check and is not the same as your debit card number. Most run 8 to 12 digits, though some banks use as few as 5 or as many as 17.
- The account type, checking or savings. Some platforms also ask for the account holder’s name exactly as the bank has it.
A few platforms add an identity step and ask for a government-issued ID or a bank statement so they can match the name.3Office of the Comptroller of the Currency (OCC). What Type(s) of ID Do I Need to Open a Bank Account? Read every digit twice before submitting.
How Long It Takes
Micro-deposits usually arrive within one to three business days after you submit your details.4Federal Reserve Financial Services. Innovation Spotlight Microdeposits Weekends and federal holidays don’t count. Submitting on a Friday afternoon means the clock effectively starts Monday.
Once they land, you don’t have unlimited time to confirm. Verification windows vary, but ten days from when the deposits post is common. Miss it and the request expires; you’ll have to start over. Check your transaction history daily during that window, because a two-cent credit is easy to scroll past.
When the Deposits Don’t Show Up
This is the most common sticking point. If nothing has landed after three business days, work through the usual causes:
- A mistyped routing or account number. One wrong digit is enough to reroute or reject the transfer.
- A mismatch between the account type you selected and the actual account. Selecting checking for a savings account, or the reverse, can cause a bounce.
- Small-transaction filtering. Some banks suppress very small credits from mobile alerts, so the deposits are there but invisible on your notifications. Pull up the full statement or call the bank.
- Timing. A request placed on a Friday or before a holiday won’t start processing until the next business day.
If none of that explains it, contact the platform that started the process. Most will let you restart. Each restart, though, resets the waiting period.
If You Enter the Wrong Amounts
Platforms usually cap you at three attempts. Blow all three and the verification typically locks, which means deleting the payment method and starting over. Some platforms make you contact support to unlock things.
The mistake most people make is rounding. A deposit of $0.07 is seven cents, not seventy. Enter the amounts exactly as they appear, decimal places included. Watch the input field too: if it already shows a dollar sign, type the cents as a decimal; if it’s a cents-only field, drop the leading zeros.
If Micro-Deposits Arrive That You Didn’t Request
Unexpected micro-deposits in your account can mean someone is trying to link it to a platform you don’t control. Treat it as a warning sign and call your bank. Ask them to note the activity and watch for unauthorized debits.
Regulation E, which implements the Electronic Fund Transfer Act, ties your liability for unauthorized electronic transfers to how fast you report them.5eCFR. 12 CFR Part 1005 – Electronic Fund Transfers (Regulation E) Report within two business days of discovering the problem and your exposure is capped at $50. Wait longer but still report within 60 days of the statement date, and liability can rise to $500. Miss the 60-day window and you can be on the hook for every unauthorized transfer that happens after it closes.6eCFR. 12 CFR 1005.6 – Liability of Consumer for Unauthorized Transfers The Consumer Financial Protection Bureau’s guidance is to call the bank the moment you spot any transaction you didn’t authorize, regardless of size.7Consumer Financial Protection Bureau. How Do I Get My Money Back After I Discover an Unauthorized Transaction or Money Missing From My Bank Account?
Faster Alternatives You May Be Offered
The wait is the main drawback of a penny test, and many platforms now offer instant verification instead. You log into your bank through the platform’s interface, often through a provider like Plaid, and the connection confirms your account in seconds. With banks that support OAuth, you sign in on the bank’s own login page, so the third-party platform never sees your password.4Federal Reserve Financial Services. Innovation Spotlight Microdeposits
The Federal Reserve’s FedNow Service adds another route: micro-deposits that clear and settle in real time. The concept is the same, but because FedNow runs around the clock, the full verify-and-confirm loop can finish in minutes.4Federal Reserve Financial Services. Innovation Spotlight Microdeposits Not every bank and platform supports the newer options, so depending on where you bank, the traditional multi-day penny test may still be your only path.