The line of numbers at the bottom of a check is what lets a bank process it. SimpleChex prints that MICR line in the E-13B font, in the position bank equipment expects, on every check — whether you use plain paper or blank check stock.
MICR stands for Magnetic Ink Character Recognition. Decades ago, checks were sorted by machines that read magnetized ink, so the characters at the bottom were printed with iron-oxide ink in a special font, E-13B, designed to be easy for those readers.
Today most checks are processed as images. When you use mobile deposit, or when banks exchange checks with each other, it's a picture of the check that travels, and the numbers are read optically. That's why the shape and position of the E-13B characters matter as much as the ink.
For most people, no. Checks deposited by phone, at an ATM that scans images, or by banks that process images are read from the picture. Standard laser toner prints crisp E-13B characters that read fine.
Magnetic MICR toner still matters in some cases: if you print a high volume of checks, if a bank tells you its equipment reads magnetically, or if you've had checks come back for MICR read errors. SimpleChex checks print the same way with a MICR toner cartridge installed — nothing in the software changes.
Inkjet printers are the weak spot. Ink can spread on plain paper and soften the edges of the characters. A laser printer is the safe choice for checks.
Both work. Plain paper is the fastest way to get started. Blank check stock — paper with security features but no bank details printed on it — adds tamper resistance and a more familiar look. SimpleChex supports standard top-check stock and lets you fine-tune the layout for the stock you buy.
Free for one business and 10 checks a month. $5/month for unlimited checks.