A voided check carries three numbers along its bottom edge, printed left to right in a fixed order: the nine-digit routing number that identifies your bank, your account number, and the check’s own sequence number. Learning how to read a voided check comes down to knowing which group is which, because employers and billers setting up direct deposit or automatic payments need only the first two. The check number on the right is for your records and theirs, nothing more.
What the Bottom Row Actually Is
That string of numbers has a name: the MICR line, short for Magnetic Ink Character Recognition. The Federal Reserve requires the characters to be printed in magnetic ink so high-speed sorting machines can read them. The order is always the same: routing number first, account number second, check number third.
Between the groups you’ll notice odd symbols that aren’t on a normal keyboard. The transit symbol brackets the routing number; the on-us symbol separates the account number from the check number. They tell scanners where one field ends and another begins. When you’re copying your details onto a direct deposit form, ignore the symbols entirely and transcribe only the digits.
The Routing Number
The first group on the left is your bank’s routing number, sometimes called a routing transit number or ABA number. It is always exactly nine digits. Every bank, credit union, and savings institution in the country has at least one, and the number tells the payment system which institution holds your account.
Inside those nine digits, the first four are the Federal Reserve routing symbol, pointing to the Federal Reserve district and processing center that handles the bank’s transactions. The next four are the institution identifier assigned by the American Bankers Association. The final digit is a mathematical check digit that lets processing systems catch typos.
If you ever want to confirm a routing number before handing it over, the Federal Reserve publishes a free online directory you can search by number or by bank name.
The Account Number
Immediately to the right of the routing number is your account number. Account numbers have no standard length — they can run anywhere from roughly six to seventeen digits depending on the bank. Two customers at the same bank will share a routing number but will never share an account number, because this is the digit string that points to your specific checking account.
Accuracy here is everything. One wrong digit and the money either bounces back or lands in a stranger’s account. Watch especially for leading zeros, which are easy to miss. If you can’t tell where the account number ends and the check number begins, cross-check against a bank statement or your online banking portal; both display the account number cleanly, separated from any check sequence.
The Check Number
The last group of digits on the far right is the check number, and it matches the number printed in the upper right corner of the check face. Its only job is to help you and your bank track individual payments. You do not need to supply it for direct deposit or any preauthorized electronic transfer. Only the routing number and account number matter for those.
Voiding the Check Without Covering the Numbers
Grab a permanent ink pen. Not pencil, not erasable ink. Write VOID in large capital letters across the face of the check, big enough that the word crosses the payee line and the amount line so nobody can fill them in later. Keep the writing above the MICR line at the bottom. If you cover those digits, you’ve defeated the whole purpose, because the person on the receiving end needs to read them.
Leave the signature line blank. A voided check with a signature on it is a document someone could try to alter. Some people run the word VOID straight through the signature line as extra insurance, which is fine as long as the bottom numbers stay clean and readable.
One point worth clearing up: writing VOID on a check is a practical deterrent, not an absolute legal barrier. Most institutions refuse to process a check marked that way, but UCC § 3-104(d) specifically excludes checks from the provision that lets a conspicuous statement strip negotiability from other instruments.1Legal Information Institute. UCC 3-104 – Negotiable Instrument Keeping the signature line blank and storing your checkbook somewhere secure matters more than the word itself.
Who You Should and Shouldn’t Give It To
Treat your routing and account numbers the way you treat any other credential. Together, they are enough for someone to initiate a withdrawal from your account by creating an unauthorized demand draft or setting up a fraudulent electronic debit, with no need to ever touch your physical checkbook.2OCC. Check Fraud: A Guide to Avoiding Losses One known scam has a fraudster posing as an employee and submitting a new direct deposit form to the payroll department, rerouting the real employee’s paycheck.
Only hand a voided check to parties you trust and have independently verified. After you submit your banking details to a new employer or biller, watch the account closely for the first couple of statement cycles and turn on transaction alerts through your bank’s app so you see any movement right away. Reporting an unauthorized electronic transfer quickly is what preserves your protections under federal law, and the clock on those protections starts from the date your bank sends the statement, not the date you read it.3eCFR. 12 CFR 1005.6 – Liability of Consumer for Unauthorized Transfers
What to Do If You Don’t Have a Checkbook
Many people never order paper checks and never need to. You can still provide the same two numbers through other means:
- Your online banking portal. Most banks show your routing and account numbers once you log in, and many offer a downloadable, prefilled direct deposit form you can send straight to payroll.
- A bank verification letter. Your bank can issue a letter on its letterhead confirming your name, account number, routing number, and account type. Some employers specifically ask for one.
- A pre-printed deposit slip. If you do have a checkbook, the deposit slips in the back carry the same routing and account numbers.
- A bank statement header. The top of a monthly statement usually shows both numbers, though not every employer accepts this as standalone verification.
Each of these produces the same two pieces of information a voided check would. What your employer or biller actually accepts varies, so ask before you prepare something they’ll refuse. And when you do submit a photo or scan, make sure every digit of the routing number and account number is sharp and fully visible; blurry uploads are the most common reason a submission gets kicked back.