The parts of a check are the labeled fields on the front (the payer’s name and address, check number, date, payee line, numeric and written amount boxes, memo, and signature), the magnetic code line printed along the bottom, the endorsement area on the back, and a set of security features built into the paper itself. Each part has a specific job, and the Uniform Commercial Code defines the check as a draft payable on demand drawn on a bank.1Legal Information Institute. UCC 3-104 – Negotiable Instrument A standard personal check measures 6 by 2.75 inches.
The Fields on the Front
The upper-left corner carries the account holder’s pre-printed name and address. This identifies whose account the money comes from. Across from it, in the upper-right corner, sits the check number, which is a reference for your own records.
Below the check number is the date line. You don’t strictly have to write today’s date. The UCC allows checks to be post-dated or back-dated without affecting validity. A post-dated check payable on demand generally cannot be cashed before the written date. If you leave the date blank, the check’s date defaults to the day it was issued.
The “Pay to the Order of” line names the person or business receiving the funds. It controls who can negotiate the check. To the right, a small box holds the numerical dollar amount, like “$1,250.00.” Below the payee line, a longer line asks you to spell out the same amount in words: “One thousand two hundred fifty and 00/100.”
When the written amount and the numeric amount don’t match, the written words control. The UCC is explicit: words prevail over numbers.2Legal Information Institute. UCC 3-114 – Contradictory Terms of Instrument Altering a spelled-out amount is harder than changing a digit, so the written line is treated as more reliable. Drawing a line through any leftover space on the written amount line keeps someone from adding extra words after you sign.
The signature line in the bottom-right corner is the single most important field. Without the account holder’s signature, no one is liable on the instrument, and banks will reject the check. The memo line at the bottom left gives you space to note what the payment is for, like an invoice number or account reference. Banks don’t process the memo line, but it’s useful for your own bookkeeping.
The MICR Line at the Bottom
The bottom edge of every check carries a string of oddly shaped characters printed in magnetic ink. This is the Magnetic Ink Character Recognition (MICR) line, and it’s what lets automated equipment sort and process millions of checks a day. The characters use a specialized font called E-13B, designed for high-speed machine reading.3U.S. Government Publishing Office. GPO Publication 310.5 – Guidelines for MICR, OCR, and OMR
The MICR line contains three main fields, each set off by special symbols:
- Routing number. A nine-digit code bracketed by transit symbols that identifies the bank or credit union. The first two digits correspond to a Federal Reserve district, the next two identify a specific Federal Reserve branch, the remaining digits pinpoint the individual institution, and the last is a check digit for error detection.
- Account number. Printed in the “On-Us” field, this tells the bank which customer’s account to draw from. Its length and format vary by institution.
- Check number. Matches the number in the upper-right corner of the check. On standard personal checks, it appears within the same On-Us field as the account number. On larger business checks, it may occupy a separate auxiliary field.
The magnetic ink is what makes the system work. Automated readers magnetize the characters and detect their signal patterns, which is more reliable than optical scanning. A check that has been crumpled, stamped, or written over can often still be read because the magnetic signal cuts through visual noise.
The Back of the Check and How to Endorse It
Flip a check over and you’ll find an endorsement area at one end, marked with printed lines and a prompt like “Endorse Here.” This is where the payee signs to authorize deposit or transfer. Below that zone, a warning reads “Do Not Write, Stamp, or Sign Below This Line” because the remaining space is reserved for bank processing stamps as the check moves through the clearing system.
The UCC recognizes several types of endorsement, and each one changes what can happen with the check:
- Blank endorsement. You sign your name and nothing else. This turns the check into a bearer instrument, meaning anyone who physically holds it can cash or deposit it. If you lose the check after signing it this way, whoever finds it can potentially negotiate it. This is the riskiest method.4Legal Information Institute. UCC 3-205 – Special Indorsement, Blank Indorsement
- Special endorsement. You sign and add “Pay to the order of [specific person].” Only that named person can then negotiate the check.4Legal Information Institute. UCC 3-205 – Special Indorsement, Blank Indorsement
- Restrictive endorsement. You write “For deposit only” above your signature, sometimes with your account number. This limits the check to deposit into your account and blocks anyone from cashing it over the counter. A bank that ignores a restrictive endorsement and pays the check inconsistently can be liable for conversion.5Legal Information Institute. UCC 3-206 – Restrictive Indorsement
The safest habit is to wait until you’re at the bank or ready to use mobile deposit before endorsing. If you must sign early, a restrictive endorsement protects you far better than a blank signature. Most banks require a specific endorsement for mobile deposit, typically your signature plus “For Mobile Deposit Only” and sometimes your account number.
Security Features Built Into the Paper
A modern check carries anti-fraud technology that’s mostly invisible during normal use. These features work together to make counterfeiting and alteration difficult:
- Watermarks. Hold a check up to light and a custom design becomes visible from either side. The watermark is embedded in the paper during manufacturing and cannot be reproduced by a photocopier or scanner.
- Chemical-reactive paper. The paper is treated so any attempt to wash or chemically alter the ink produces visible stains or discoloration.
- Microprinting. Tiny text runs along the signature line or borders. It looks like a thin line but reveals legible words under magnification. Photocopiers and scanners can’t reproduce text this small, so copies appear as a solid line or a blurred streak.
- Security screens. A patterned background woven into the check that distorts when photocopied, making counterfeits obvious.
- Fluorescent fibers. Invisible threads embedded in the paper glow under ultraviolet light, helping banks authenticate originals.
Not every checkbook includes all of these features. Checks ordered through your bank or a reputable printer generally carry more security layers than the cheapest options online.
How Long a Check Stays Valid
A bank has no obligation to honor a check presented more than six months after its date.6Legal Information Institute. UCC 4-404 – Bank Not Obliged to Pay Check More Than Six Months Old After that, the check is “stale-dated.” The bank isn’t required to pay it, but it’s allowed to if it acts in good faith. In practice, many banks will still process a stale check without flagging it, which means the money can leave your account unexpectedly if an old outstanding check surfaces later.
How to Void a Check
Use a pen with permanent ink and write “VOID” in large letters across the front, covering as much of the check face as possible. The goal is to make the check unusable while keeping the account and routing numbers legible, since voided checks are commonly requested to set up direct deposit or automatic payments.
Record the voided check’s number in your register so it’s accounted for. If you’re discarding the check rather than submitting it somewhere, shred it or cut directly through the account number, routing number, and signature area before throwing it away.
How Business Checks Differ
Business checks look noticeably different. They typically measure a full 8.5 by 11 inches and include the check itself along with one or two detachable voucher stubs. The stubs act as built-in record-keeping, itemizing what the payment covers with invoice numbers, purchase order references, or payroll breakdowns. The payee tears off the stub for their records, and the issuing company keeps a copy.
Many businesses also require two signatures on checks above a set dollar threshold as an internal control. The check portion carries the same fields as a personal check, but the extra real estate allows for more detailed formatting that feeds directly into accounting software.