The UK digial bank has followed its peers Monzon and Starling into the black as the funding slowdown pushes the new breed of challengers to seek out profitable business models.Atom, which does not offer current accounts, has seen its business boosted by high interest rates and attractive savings products, recording retail savings balances of more than £5.7bn funded by a quarter of a million customers.The Durham-based lender posted a pretax profit of £7m for FY24, compared with a £10m loss last year. Atom’s operating profit surged 600 per cent year on year to £27m.Mark Mullen, CEO, says: "We begin the new year with tailwinds in the form of strong asset pipelines, excellent technology, a highly engaged team, supportive investors and an enviable reputation with customers. The change in sentiment regarding the interest rate outlook will create new pressure on spreads which we will need to monitor closely. In the year ahead it’s likely that we will very carefully balance growth with profitability."Atom is also eyeing the IPO opportunity, with Mullen telling CityAM: “I don’t want to be hostage to it. We still have a way to go to get bigger. One year’s full profit is great, but give us another one. Let’s demonstrate to our investors that this is not an interest rate trick and we’ve created an actual sustainable business.”