Yes, it is generally permissible for you to print a business check on a
personal (consumer) check sized (6" x 2-3/4") piece of paper.
As an example, you can order business checks in that size from TechChecks.
"Wallet-size checks are perfect for home or small business accounting needs."
There are some things to take into account before printing those checks, such
as the proper ink to use for that row of numbers at the bottom of the check.
These numbers are known as "Magnetic Ink Character Recognition" or MICR and
the "ASAP Checks, Forms & Supplies" website has a Frequently Asked Questions
(FAQ) page on the subject.
"The check processing system is based on the special numbers and symbols on the
bottom of checks (MICR) to be recognized magnetically by devices called
reader/sorters. Dot matrix, inkjet and many laser printer inks and toners have
*no* magnetic properties. Some laser printer toners have limited magnetic
properties, but well below what the standards call for, and without being
formulated for passing through reader/sorters as many as 30 times (another
There is at least one reason that you should avoid "plain" paper, as outlined
by this About.com article on printing your own checks.
"You should also use special paper for check printing. This paper has security
features that make it difficult to alter your printed check."
The About.com site also has a page titled "How to Write a Check That is Hard to
Alter" that you might find useful.
There is also the somewhat esoteric world of Automated Clearing House (ACH)
that might need to be considered.
"To prevent business checks from conversion into ACH transactions (electronic
payments) you must use business checks that contain the auxiliary on-us field
on the far left of the business checking MICR Line."
The above might come into play in your circumstances in that a check that is
of a "personal size" might not be wide enough to include the "auxiliary on-us
field" mentioned above.
The final, and certainly not least thing to consider is whether your bank has
no problem with the final format of the check that you want to print. If the
format is one that prevents it to be processed through their scanning device
then they might apply processing fees. Your bank is probably the final arbiter
of the check format.
If you need any clarification, pleaae feel free to ask.
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