Reacting to the publication of the CMA's final report, Paul Pester, CEO of TSB, said:
"The CMA has played right into the hands of the big five banks and missed a golden opportunity to enable people across the UK to get a better deal from their banks.
"Whilst we're pleased the CMA has committed to delivering TSB's Credit Passport through an open API - which will open up the switching service to all consumers - the CMA has failed to make strong recommendations to bring real transparency to banking.
"Banking must be the only industry that doesn't tell its customers how much they are paying for their services. Consumers need to be equipped with the necessary tools in order to make informed choices about the best products and services for their needs. This is why we will continue to champion transparency over the true cost of banking through the creation of a Monthly Bill.
"The CMA's report is only the first rung on the ladder and, while disappointing, it should not constrain the Government in its ambition to achieve a truly competitive banking market.
"At TSB, our focus remains unchanged: we will continue to do our bit to bring more competition to UK banking and ultimately make banking better for all consumers."