MICR refers to the formulation of magnetic toner or ink used to print the special font at the bottom of checks. Different from regular ink or laser toner, MICR ink and toner contain magnetic iron oxide, a requirement of the Federal Reserve, making check-clearing a more efficient process.
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According to the Federal Reserve and the Accredited Standards Committee, X9 Inc. for financial industry standards, a check must contain MICR for it to be treated as a cash item.
If your business is currently printing its own checks, you must use proper MICR toner or ink to ensure they are compliant with the processing procedures of the banking system.