I know that Redwood Credit Union and UNIFY Financial Credit Union offer such cards. Not too many financial institutions in this day and age offer fixed-rate credit cards.
IMHO, you should be looking at institutions with a record of low Credit Card Interest rates. If interest rates go up significantly, it is very unlikely the so called fixed Credit Card Interest rates will hold.
Seems to me a CU with a Fixed Rate Credit Card would likely charge close to the Legal Max.
I currently have a fixed-rate credit card from Redwood Credit Union. My RCU credit card’s current purchase APR is 8.99 percent. An RCU representative has told me the following:
The only realistic circumstances I can think it would change (and this would be for the worse) is if your credit score were to decline and you were to apply for a limit increase.