What is Affirm's Customer Service Number? Rui Kojima April 30, 2021 14:23 Updated To contact Affirm directly, you can contact their customer service team at 1-855-423-3729. Related articles How do returns work when I use Affirm to make a purchase? What is Affirm? Does Affirm do a credit check and will it affect my credit score? How do I make payments with Affirm? How do I make an exchange on my order? Comments 0 comments Article is closed for comments.