PrintCHECK guide
What is a MICR line? Reading the numbers at the bottom of a check
The strip of odd-looking numbers along the bottom of a check is the MICR line. It is how banks read a check automatically — and getting it right is the one part of printing your own checks that is not optional.
· 6 min read · By the Consus Solutions team
MICR in one paragraph
MICR stands for magnetic ink character recognition. The characters are printed in a font called E-13B, traditionally in ink or toner containing iron oxide, so that sorting machines can read them magnetically even through stamps, signatures or smudges. In the United States and Canada, E-13B is the standard.
What the numbers mean
E-13B has the ten digits plus four special symbols that mark where each field begins and ends. On a typical business check, reading left to right, you will find:
| Field | What it is |
|---|---|
| Check number (auxiliary on-us) | Often printed first on business checks, between on-us symbols |
| Routing number | Nine digits identifying the bank, between two transit symbols |
| Account number | Your account at that bank, followed by an on-us symbol |
| Check number (on personal checks) | Printed after the account number instead |
| Amount | Encoded later by the bank of first deposit, on the far right |
The clear band
The bottom 5/8 inch of a check is the clear band. Only MICR characters belong there. A signature line, a stub perforation or a stray bit of text in that strip can make the check hard for the bank's equipment to read, which means rejected items and manual handling.
Printing MICR checks yourself
- Software that prints E-13B correctly, at the right size and position. PrintCHECK builds the line from your bank account settings and warns if other fields stray into the clear band.
- Blank check stock with security features such as microprinting and a void pantograph.
- A laser printer. Many banks recommend MICR toner for the magnetic line; ask yours what it expects.
- Your bank's details: routing number, account number and the fractional routing code printed near the check number.
Before switching over fully, print a few checks and ask your bank to test them. Most banks are happy to, and it is the quickest way to confirm your setup.
Why print MICR checks at all?
Pre-printed checks tie each box of paper to one bank account and one starting number. With blank stock and MICR printing, a single stock serves every account, a change of address does not mean reordering, and you stop throwing away unused checks.