TSB and the Co-operative Bank both swung to a profit in the first six months of the financial year after cutting costs.
The Co-op Bank turned a £44.6 million pre-tax loss in the opening six months of last year into a £21.4 million profit this time round.
Meanwhile, TSB swung from a loss of £65.5 million to a £42.9 million profit.
Both banks managed to increase their incomes while cutting costs, which was then reflected in their bottom lines.
TSB chief executive Debbie Crosbie said: “With a relentless focus on what our customers want and innovating to serve them better, we have grown our balance sheet and increased income, while reducing operating costs further.
“I want to thank everyone at TSB for their efforts in supporting our customers and communities, helping them feel more money-confident, and in driving TSB’s wider contribution in the first half of the year.”
Co-op Bank boss Nick Slape said the company is well on its way to “sustainable profitability”.
“I am delighted to report that the relentless focus on delivering our plan is driving a strong financial and operational performance for the bank,” he said.
“As a result of a disciplined approach to cost alongside taking opportunities swiftly as they arise, we have delivered a second consecutive quarter of underlying and statutory profit.
“We have made excellent progress against the strategic priorities that we outlined at the end of 2020, remaining firmly on track to deliver our full-year guidance and to return the bank to sustainable profitability this year.”
Co-op Bank said it had managed to cut costs by 9% compared with a year ago because of efforts to simplify its business. The company completed a restructuring last year.