If you paid a bill from last year with this year's Discover credit card, it is likely that the payment will be credited to your account and applied to your current balance. However, if the payment was for a bill due last year, it may need to be reflected on your current statement or account balance. Instead, it may appear as a credit or adjustment on a future statement. Suppose you have any questions or concerns about the payment. In that case, I recommend contacting Discover directly to inquire about the status of the payment and how it was applied to your account. They should be able to provide you with more information and help resolve any issues you may have.