How to Tell If a Signature Is Forged

Updated February 21, 2017

A forged signature exposes the victim to undesirable circumstances. In the case of a forged signature on a check, for instance, the individual who unknowingly attempts to cash it is subject to bank fees, penalties and the possibility of the bank suspending the account. Fortunately, with close examination, it is possible to determine the authenticity of a signature.

Compare a document containing an original signature to one containing the suspicious signature, if possible, and take note of your initial impression. Usually, something about a forged signature will look odd.

Measure the length of both signatures. says that a person's signature remains the same length always, even if the handwriting changes. A forged signature may be longer or shorter than the original.

Look for small breaks in the suspicious signature. According to, signature forgers pause during the process of copying the signature to examine the genuine copy. When they do this, they may lift the pen off the paper. This causes spaces between the letters that are slightly larger than usual. The beginning stroke of the next letter will be heavier.

Check for ink blots. While pausing to examine the genuine signature, the forger may inadvertently press down on the paper. This will form tiny dots in the signature if he is using a ballpoint pen.

Look for shaky lines in the signature. refers to these as "criminal-tremors." This occurs when the forger holds the pen tightly due to intense concentration.


According to the U.S. Department of Treasury, banks process checks with machines so they cannot manually examine them to ascertain the authenticity of the signatures. It is the customer's responsibility to ensure that a check is genuine.

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About the Author

Tina Amo has been writing business-related content since 2006. Her articles appear on various well-known websites. Amo holds a Bachelor of Science in business administration with a concentration in information systems.