The ability to pay a traffic ticket fine with a credit card varies by state and by county, as DMV.org explains. DMV.org provides the policies and procedures for traffic ticket payment in each state, searchable by zip code.
Most counties in Alabama accept money orders or cashier's checks as payment for traffic tickets; not all accept payment using credit cards. In Louisiana, those paying for traffic tickets must contact the appropriate court to learn what the fine is, since the state does not print fine amounts on the tickets; some courts accept credit cards, while others only accept cash or money orders. New Hampshire, on the other hand, accepts credit card payments for all traffic tickets.