The latest change means the mutual is no longer offering the sub-four per cent mortgage deals it did last month. 

Rates now begin at 4.19% for a five-year fixed remortgage deal at 60% loan-to-value (LTV). This has a £999 fee and was previously 3.99%. The fee-free option is priced at 4.39%. 

For new homemovers and first-time buyers, the five-year fixed product at the same LTV tier with a £999 fee has a rate of 4.24%, a 0.1% increase. The fee-free homemover option is priced at 4.44% and the first-time buyer product has a rate of 4.54%. 

Swap rates swinging upwards

A spokesperson for the mutual said it needed to ensure its mortgage pricing was “sustainable at a time where swap rates, on which mortgage pricing is based, continue to fluctuate”. It noted that swap rates had began to rise recently. 

Rates have been increased by between 0.05% and 0.21%. 

Henry Jordan, director of home at Nationwide Building Society, said: “Over the last few months, we have continued to lower rates across our mortgage range, including doing so four times this year.  

“However, given the recent increase in swap rates, we are having to make some small increases on selected mortgage rates this week so that we can continue to balance our support for all types of borrowers with the need to ensure our rates remain sustainable.” 

Mindful of wholesale costs 

Reacting to the news, mortgage industry insiders said the rate increase was inevitable as market conditions had changed. 

Steven Morris, advising director at Advantage Financial Solutions, said the cost of borrowing money had risen by 0.3% to 0.4% in recent weeks. 

He added: “Given this is a problem being faced by all lenders offering fixed rate mortgages, it seems inevitable others will follow suit, at least to some extent. For now, we hope these changes are things ‘settling down’, rather than a total U-turn on the recent rate cuts we have seen so far in 2023.” 

Justin Moy, managing director at EHF Mortgages, said lenders would be affected by the further Bank of England base rate rise pencilled in for March. 

“Analysts still predict that the base rate will fall towards the end of the year, but there may be some bumps along the way,” Moy added.