The ABS lending indicators data showed fixed-rate home lending hit $4.5 billion in June, up from $2.635 billion in May.
This includes existing borrowers refinancing.
As a share of all home loan activity, fixed-rate lending made up 8.18% of the pool in June, up from 4.88% the month prior.
The proportion of fixed-rate lending is still well down from the peak of more than 55% in mid-2021.
ABS' head of finance statistics Mish Tan said the elevated level of refinancing was due to rising interest rates.
"The value of total refinancing between lenders was 12.6% higher in June compared to a year ago," Ms Tan said.
The value of refinancing in seasonally adjusted terms was $20.18 billion in June, down slightly from the May all-time peak.
New lending excluding refinancing was $24.6 billion, down 1% on the month.
The push to refinance could lead to average interest rates decreasing in the fixed-rate lending space, despite RBA rate hikes, as borrowers sniff out better deals when looking to refinance from a variable rate.
For new loans written in May, investors who fixed for 3 or more years in May found their rate 48 basis points (0.48%) lower than those who would have locked-in in April.
For the average investor home loan size of $597,000, that's an extra $178 per month on a 25-year home loan.
While home lending is up from its February lows, off the back of higher home prices, Westpac senior economist Matthew Hassan questioned if it was sustainable.
"Price gains continue to come off low volumes and even lower listings, meaning the upturn may be susceptible to stalling if demand softens and ‘on-market’ supply lifts," Mr Hassan said.
See Also: More Home Loan Statistics
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