Our customer had three fraudulent checks presented against their account. We have attempted to send them back to the paying bank even though we've missed our deadline for doing so (in the hopes that maybe they would honor the return). What is the deadline for the paying back to dishonor our return? We are in a holding pattern with our insurance company until we receive word back from the paying bank.

Are we required to reimburse our customer now, or can we wait until we find out about the return?

Your obligation to your customer depends on your state's UCC, your deposit agreement, and the timeliness of your customer's claim. The depository bank's acceptance or rejection of your late return will not have a bearing on your liability to your customer.