Underlying pre-tax profit rose to £50mln in the year to 31 December 2018 from £21mln a year ago, although growth softened as the final quarter progressed. Analysts had forecast underlying pre-tax profit of £58mln.
Customer loans gained 48% to £14.2bn with the fourth quarter adding £1.1bn.
Deposits rose by 34% to £15.7bn following quarterly growth of £848mln.
Total assets amounted to £21.7bn, up 32% on last year.
Risk-weighted assets at full year are expected to reach £8.9bn while the capital ratio is estimated to be 15.8%.
Metro Bank attracts new customers as it opens new branches and invests in online banking
The challenger bank said the fourth quarter continued the trend seen in the previous three quarters with the addition of 100,000 new customer accounts as it invested in new stores in prime locations and improved its digital offering.
Metro Bank opened stores in Bath, Crawley, Northampton, Putney, Ashford, and Piccadilly during the quarter and opened another store in Moorgate in January.
A further seven stores are in advanced planning stages or under construction.
In contrast, the UK's biggest banks including Lloyds Banking Group PLC (LON:LLOY), Royal Bank of Scotland Group PLC (LON:RBS) and Barclays PLC (LON:BARC) have been closing branches in response to more customers banking online.
"2018 was another strong year of growth for Metro Bank as we continued to invest in both new stores and digital capabilities to win customers, deposits, assets and to create fans," said chief executive Craig Donaldson.
"Metro Bank remains well positioned to support our growth strategy as we navigate an uncertain period for the UK."
In morning trading, shares were changing hands at 1,603p each.
Higher rates create 'perfect storm' for banks, says analyst
AJ Bell investment director Russ Mould noted that the fourth quarter profits slipped and the market will want an explanation of what's happened when the bank posts its full numbers in February.
He said intense competition in the mortgage market could be a key reason behind the recent slowdown.
Mould added that savings rates have been rising as the Bank of England gradually lifts the base interest rate.
“This has created a perfect storm for some banks and is likely to have put pressure on Metro Bank’s net interest margin, which compares the money paid on savings to the interest customers pay on loans," he said.