Homeowners are taking advantage of lower interest rates, rushing to refinance their mortgages before rates potentially turn higher again.

Total mortgage application volume increased 2.4% last week from the previous week and was up 15% from a year earlier, according to the Mortgage Bankers Association's seasonally adjusted index.

Refinances drove the numbers, jumping 8% for the week to the highest pace in a month and 31% annually.

Refinance volume is highly rate-sensitive each week; the average contract interest rate for 30-year fixed-rate mortgages with conforming loan balances ($484,350 or less) decreased to 4.33% from 4.40%, with points increasing to 0.43 from 0.40 (including the origination fee) for loans with a 20% down payment.

"Mortgage rates fell for the fourth straight week, with the 30-year fixed rate mortgage hitting its lowest level since January 2018, leading to a rebound in refinances," said Joel Kan, MBA's associate vice president of economic and industry forecasting. "Once again there was an increase in average refinance loan sizes, as borrowers with larger balances responded accordingly to lower rates."