Frequently Asked Questions

What is actually in this box?

One sealed black MICR cartridge, built on the CE390A platform — the cartridge HP also calls the 90A — but filled with magnetic toner instead of standard toner. That fill is the entire point: it exists for printing the machine-readable line along the bottom of checks.

What makes MICR toner different from a regular 90A?

The toner carries magnetic material that bank sorting equipment reads as the check clears. A standard cartridge prints a line that looks identical to the eye but cannot be read by those machines — which is why check stock and ordinary printing should never share a cartridge.

Which jobs belong on this cartridge?

Payroll checks, accounts-payable checks and deposit slips — work whose bottom line must survive bank processing. Everyday documents belong on a standard CE390A; the working pattern is to keep this MICR unit for check runs and swap back afterwards.

Is bank acceptance guaranteed?

It is not, and no honest seller can promise it. Before a first full run, print a small test batch and confirm readability with your bank — reader settings and check stock vary, and a five-minute test protects an entire payroll.

Which printers does it fit?

The LaserJet Enterprise 600 M601, M602 and M603 printers and the M4555 multifunction family, including the Enterprise M4555f — the same machines the standard 90A serves, fitted in the same two-minute swap.

What are its rating and cover?

It is rated at 10,000 pages at standard coverage, and it carries a 1-year warranty and 1-year free returns: damaged on arrival or failing early means replacement or refund. Support is available Monday through Friday, 9 AM to 5 PM CST.

About This HP 90A-MICR Cartridge

At $153.59, this single MICR cartridge is a specialist tool: one CE390A (90A) unit with magnetic toner, kept for the check runs a standard cartridge cannot serve. Print a test batch and clear it with your bank before relying on it for a full payroll. We ship from warehouses in IL, PA, GA and CA; the shipping & returns page sets out delivery and returns, and the standard-toner range sits under HP.