Ulster Bank has reported pre-tax profits of £18m for 2019, down nearly 65% from £51m a year earlier.
The lender said its profitability had been hit by investment in the business and the voluntary refund of interest to business customers.
A charge of £10m was incurred from the refunds and associated costs. However, the bank said it had seen a 12% increase in new corporate lending, and an 8% growth in new small business lending.
It had total income of £189m, compared to £191m a year before. The bank said the figures reflect most but not all of the profits generated in Northern Ireland by Ulster Bank, which is part of the Royal Bank of Scotland group.
Ulster Bank has 44 branches here.
Mark Crimmins, head of NI for Ulster Bank, said: "This has been a solid year for Ulster Bank in Northern Ireland, with a strong underlying business performance allied to significant and visible investment in the bank to enable us to provide even better service to our customers.
"Despite a challenging external environment and subdued borrowing appetite from businesses, we increased corporate lending in 2019 by 12% and saw a 8% increase in small business drawdowns."
The bank recently announced around 100 new contact centre jobs and a multi-million pound refurbishment of its Belfast headquarters as it shifts its contact centre from Danesfort in south Belfast.