According to new research conducted by Canstar, these borrowers will absorb the 4% increase in cash rates recorded over the past year.

The latest estimates from the Reserve Bank of Australia (RBA) show that half of all fixed-rate home loans will mature in 2023 as borrowers switch from low fixed rates to higher variable rates.

Borrowers who took out a two-year fixed-rate loan at 2.21 percent in 2021 are now coming due, and based on an average variable rate of 6.57 percent, repayments on a $500,000 loan would increase by $1,200 to $3,101 per month.

Similarly, those borrowers who opt for a three-year fixed rate of 2.61% in 2020 will soon face an estimated 53% repayment increase from $2,004 to $3,074 per month on a $500,000 loan.

Canstar's Steve Mickenbecker said the arrival of July means borrowers could see their payments spike overnight, and there are concerns that many may not be able to continue paying their loans.

"Fixed-rate borrowers have not adapted to higher rates over the past year. They have avoided the pain of adjusting their budgets for higher loan repayments, but will take a huge hit from the Reserve Bank's 12 cash increases in the past year.

"To help cope with the inevitable higher repayments, any borrower still on a fixed term should make the necessary adjustments now and bring forward their extra repayments.

"The latest inflation data is encouraging and may be enough for the Reserve Bank to stay its hand when it raises the cash rate again in July. If stronger quarterly inflation data released in July do not confirm the trend towards the Reserve Bank's 2% to 3% inflation target, we can expect further rate hikes.

Borrowers with fixed-rate loans have a number of ways to reduce their higher loan repayments.

These methods include moving to loans that offer the lowest rates and seeking better deals from their current lenders or competitors.

Mr. Mickenbecker cited the example of a borrower who could save up to $397 per month on a $500,000 loan at a low rate of 5.24 percent - even with a value rate of 80 percent.

"Fixed-rate borrowers whose loans mature this year should check their loan contracts today to find out what rates they can expect when the fixed term ends and check with their lenders," Mickenbecker said." Most people will be suitably shocked."

"Refinancing to one of the lowest rate loans will ease the burden of higher repayments and is a must for every borrower. It won't take the pain out of repayment altogether for borrowers, but it will provide hundreds of dollars that don't have to be found elsewhere in the household budget.

"For many borrowers, the path to refinancing will be closed and they are in no financial position to appeal to a new lender. It is imperative that they talk to their lender before the fixed rate expires to understand their repayment situation and discuss their options.