MICR History, Technology & Check Printing Specifications

MICR, or Magnetic Ink Character Recognition, is a technology developed to help financial institutions identify and process checks efficiently. It combines specially designed MICR characters with magnetic printing material so information printed in the MICR line can be recognized by compatible check-processing equipment.

Today, MICR is most commonly associated with the routing number, account number, check number, and special symbols printed along the bottom of checks. Businesses using compatible laser printers can produce these characters with specially formulated MICR toner.

For a beginner-friendly explanation of MICR, the MICR line, fonts, and printing checks, visit our MICR Guide & Check Printing FAQ.

The History of MICR

The history of MICR dates to the 1950s, when the banking industry was looking for ways to automate the growing task of sorting and processing checks. As check volume increased, older manual and mechanical sorting methods became increasingly inefficient.

Before MICR became widely used, banks relied on methods such as Top Tab Key Sort and Sort-a-Matic to organize checks.

Top Tab Key Sort

The Top Tab Key Sort method used punched holes along the top of checks. The location of the holes represented numerical information. A sorting key could be inserted through the appropriate holes to separate groups of checks and help place them into numerical order.

Sort-a-Matic

Sort-a-Matic used a series of numbered dividers to sort checks in stages. Checks could be grouped according to portions of the account number and then sorted repeatedly until they were placed into the desired numerical order.

These processes required substantial manual handling. As computers and automated processing became more practical, the banking and technology industries developed methods that could encode information directly on checks for machine-assisted processing.

How MICR Changed Check Processing

Magnetic Ink Character Recognition provided a standardized way to place machine-readable banking information directly on a check. Instead of relying entirely on manual sorting methods, compatible equipment could recognize information encoded in the MICR line and use it during check processing.

This helped make large-scale check processing faster and more efficient and established the familiar MICR line still seen along the bottom of checks today.

What Is the MICR Line?

The MICR line is the row of specially formatted numbers and symbols printed along the bottom of a check. Depending on the check layout, the line can include the bank routing number, account number, check number, and other information used during check processing.

MICR characters must be printed clearly and positioned correctly. Businesses printing checks in-house should use the appropriate MICR font, check layout, printer, toner, and check stock for their check-printing system.

What Fonts Are Used for MICR Printing?

Two well-known character sets associated with MICR are E-13B and CMC-7. These fonts use specially designed numbers and symbols that can be recognized by compatible MICR processing equipment.

E-13B is commonly associated with checks in the United States, while CMC-7 has been used in various other banking systems around the world.

A MICR font alone does not make ordinary printing into MICR printing. The MICR line also requires appropriate positioning and, when magnetic recognition is required, the proper magnetic printing material.

What Are MICR Specifications?

MICR specifications address characteristics that help the MICR line remain readable and consistently positioned. These include character shape, print quality, alignment, spacing, and placement of the MICR fields along the bottom of a check.

The MICR line should print clearly without missing portions of characters, excessive fading, unwanted marks, or other print defects that could interfere with recognition.

Check layouts also use defined MICR fields. These can include the Auxiliary On-Us Field, Transit Field, On-Us Field, and Amount Field, depending on the document and application.

Why MICR Print Quality Matters

MICR check printing depends on more than simply placing routing and account numbers at the bottom of a page. Character positioning, print density, magnetic signal strength, check stock, and overall print quality can all affect the finished MICR line.

Characters with voids, breaks, fading, poor alignment, or incorrect positioning can create processing problems. This is why businesses printing checks should periodically inspect their MICR output and use supplies intended for their particular check-printing setup.

From Magnetic Ink to MICR Toner

The name MICR still stands for Magnetic Ink Character Recognition, but businesses using laser printers typically print with toner rather than liquid ink.

MICR toner is specially formulated magnetic toner used in compatible laser printers. The toner cartridge must be matched to the particular printer model being used for check printing.

This development helped make in-house MICR check printing practical for businesses using office laser printers rather than specialized commercial printing equipment.

Shop MICR Toner by Printer Brand

Laser Cartridge Plus has supplied MICR toner and check printing supplies since 1995. Choose your printer or MICR cartridge brand below to find compatible MICR toner for your equipment.

For a complete brand-by-brand shopping guide, visit our MICR Toner for Check Printing page.