What number do I call if I have a question or problem with my online bill payer? For the most specific expertise about bill payer, please call 1-844-697-5600 to speak with a CheckFree bill pay service representative. They are available 7 days a week, from 7AM-1AM. Have more questions? Submit a request 0 Comments Please sign in to leave a comment. Related articles What is the cut off time for processing regular bill payments?