With which colors can one fill out and sign and personal check in the US?
Black is of course okay; I have heard that blue is also allowed. An ideal answer will give references.
Is there anything else to know? Does the answer follow from more general rules about the issuing and signing of legal documents in the US?
Keep in mind that many checks are being cashed via scanner or photo. These can be home based, business based or ATM based systems. The key requirement is that the software has to be able to distinguish the "written" parts from the background parts.
If the image doesn't have enough contrast for the edge detection to work, the check can't be easily processed. In that case a human looks at the image and decodes the image and processes the transaction. The image is not in color.
Many businesses scan the check and hand the original back to you after having the Point of Sale system process the image.
Post 2001 the checks in the united states are no longer moved through the banking system, only their images. With the roll out of these image based systems, in the future almost no physical checks will be seen by banks. Therefore the actual ink color is not important, only the result.
