Forgery involves the making, altering, use, or possession of a false writing in order to commit a fraud. ... Forgery (also known as "uttering a false instrument") is a serious offense, punishable as a felony in all fifty states and by the federal government.

What is considered altering a check?

An altered check is a check or another negotiable instrument that has been materially and maliciously altered to effect a fraud. Usually, either the name of the payee, the amount of the check, or the date is changed.

Is it illegal to modify a check?

Errors on a check could include a misspelling of your name or the check being written to a different name. It is illegal to correct any error on a check on your own. Fortunately, there are other methods of correcting the error so you can still cash or deposit the instrument.