The FCA has forced Cheque Centre, which has 451 branches across the UK, to stop making the short-term loans -- under what is termed a voluntary agreement.
The business was the second biggest payday lender on the High Street, making it the FCA's most high profile target since it took over the regulation of payday lenders last month.
The watchdog was unhappy about the extent of checks on what borrowers could afford and on the treatment of customers in financial trouble.
Cheque Centre has been criticised in newspapers for targeting desperate families who couldn't repay, a charge which it denies.
It will carry on with its parallel businesses of pawn broking and selling foreign currency.
A spokesman from Cheque Centre said: "The FCA made clear their expectations, under the new rules, and we offered to make immediate changes. One of the decisions we made was to accelerate our exit from payday lending."