Truth in Lending: § 1666i-1. Limits on interest rate, fee, and finance charge increases applicable to outstanding balances [TILA § 171]
(a) In general
In the case of any credit card account under an open end consumer credit plan, no creditor may increase any annual percentage rate, fee, or finance charge applicable to any outstanding balance, except as permitted under subsection (b).
(b) Exceptions
The prohibition under subsection (a) shall not apply to—