The Credit CARD Act of 2009 limited late payment fees that credit card companies can charge. There are two ways that the fee is limited: first, the fee cannot be larger than the amount of the payment. For example, if your minimum payment is $15, the late fee can be no more than $15. Second, the Act requires Federal agencies to set maximum late payment fees.
When the Act first took effect, the late payment fee maximums were set at $25 for the first offense, and $35 for subsequent offenses within 6 months of the first offense.
The Bureau of Consumer Financial Protection updated these fee maximums last year, which took effect on January 1, 2015, to $27 and $38.
From the Federal Register / Vol. 79, No. 158 / Friday, August 15, 2014 / Rules and Regulations:
Effective January 1, 2015, the permissible fee threshold amounts
are $27 for Sec. 1026.52(b)(1)(ii)(A) and $38 for Sec. 1026.52(b)(1)(ii)(B). Accordingly, the Bureau is revising Sec.
1026.52(b)(1)(ii)(A) and (B) to state that the fee imposed for
violating the terms or other requirements of an account shall not
exceed $27 and $38 respectively.
12 CFR Part 1026 is also called Regulation Z and is the regulation that deals with consumer credit. Section 1026.52(b) is the section that regulates penalty fees.
Specifically, 1026.52(b)(1)(ii) says:
A card issuer may impose a fee for violating the terms or other
requirements of an account if the dollar amount of the fee does not
exceed, as applicable:
(A) $27
(B) $38 if the card issuer previously imposed a fee pursuant to paragraph (b)(1)(ii)(A) of this section for a violation of the same type that occurred during the same billing cycle or one of the next six billing cycles;
...
(D) The amounts in paragraphs (b)(1)(ii)(A) and (b)(1)(ii)(B) of this section will be adjusted annually by the Bureau to reflect changes in the Consumer Price Index.
When these regulations are updated, there is a notice in the Federal Register, which is what is quoted above.
The cap can be adjusted annually for inflation. (Editor's note: The late-fee cap rose to $26 in 2014).