About a year ago I transferred money to a chase credit card with a promotional rate of 4.9% until it is paid off. Now the credit card company is changing the rules, they are keeping the 4.9% rate, but adding a $10 a month charge to keep that rate and they are making me pay 5% of what I owe each month as a minimum. When I called they said I could opt out of that promotion and switch to a 7.9% rate, and then they would drop the $10 monthly charge and I would only have to pay 2% of what I owe.

Can they change the promotion like that? Is this legal?

Does it say anywhere in the contract that rates can be changed if given notice? Most of them will.