Is 636 a good or fair credit rating

It depends on what loan program you are trying to be approved for at this time. Also is that one score or part of two or more scores?

More info needed.. Understand it takes more than a credit score to obtain financing.. I've seen borrowers with a 780 score have certain deficiencies which prevent them from getting financing.. and likewise, I've had borrowers with lower scores than yours qualify.. the short answer is yes.. there are loan programs which have minimum qualifying credit scores lower than yours.. But can you qualify for a loan?? You have to apply to find out.. The best advise I can give you would be to reach out to a local mortgage broker and apply with them.. once they see your complete loan profile, they can advise you.. I'm a Broker here in Scottsdale AZ and I only lend in Arizona. If you or someone you know is looking for financing options, feel free to contact me or pass along my information. William J. Acres, Lender411's number ONE lender in Arizona. 480-287-5714 WilliamAcres.com NMLS# 226347

Unfortunately, that score is considered weak, and well below the current national average. It is too low for many many loan programs, yet perfectly find for many other mortgage loan programs. If you get financing, you will likely pay a higher rate. If you need to act now, just go ahead and apply, but if you have time to work on improving your score, it would be wise to do that first.