Homeowners could face hundreds of pounds in extra interest if delays in completing remortgage paperwork leave them on lender SVRs, according to conveyancing firm RG Law.

The firm’s analysis suggests a four-week delay could add approximately £138 in interest on a £150,000 mortgage, £230 on a £250,000 mortgage and £322 on a £350,000 mortgage.

The illustrative figures are based on the difference between Moneyfacts’ October 2026 average standard variable rate of 7.13% and average two-year fixed rate of 5.93%.

The calculations assume the mortgage balance remains unchanged and exclude fees, with actual costs depending on individual circumstances and the replacement deal available.

RG Law said delays can arise when identity documents remain outstanding, client forms are incomplete or signed mortgage deeds are returned late.

Other requirements, including redemption figures from the existing lender and information from freeholders or managing agents for leasehold properties, can also affect completion times.

The firm is urging homeowners to prepare their paperwork early and ensure all necessary information is provided as soon as possible to help prevent avoidable delays.

Karen Marsh of RG Law said receiving a mortgage offer was an important milestone but did not necessarily mean a case was ready to complete.

“Completing on time can help homeowners avoid an unnecessary period on their lender’s standard variable rate,” she said.

“Different stages depend on information from borrowers, lenders and other organisations. We focus on what we can influence: progressing the legal work promptly, giving homeowners clear instructions and dealing with queries as they arise.

“Brokers and lenders put considerable work into securing the right mortgage for their clients. Our role is to support that work through to completion, keeping everyone informed and helping resolve outstanding requirements.”

UK Finance estimates that around 1.8m fixed-rate mortgage deals will end in 2026, while the Intermediary Mortgage Lenders Association forecasts £110bn of remortgage lending in 2027.