Nearly 40 per cent of mortgage holders say they have not switched lenders in the past decade in search of cheaper rates, according to comparison service Finder.

If these 1.17 million households made the effort to switch or negotiate and grab a variable home loan rate at just 0.1 percentage point below the current average 5.2 per cent, they could each save $8415 over a 30-year loan term.

That is based on the national average mortgage size of $379,400. Some customers may be able to get the bank to lop off an entire percentage point.

"We're seeing the cheapest home loan deals ever and it's now more affordable to switch lenders since the banning of excessive exit fees to variable home loans in 2012," said Finder's consumer advocate Bessie Hassan.

"Despite this, refinanced loans represent 34 per cent of all home loans financed, according to the Australian Bureau of Statistics Housing Finance data. That figure has fluctuated between 31 and 34 percent since the credit reforms were introduced [showing little impact]."

The average variable rate of the Big Four banks has jumped to 5.61 per cent, which is 0.4 percentage points higher than the overall average.

There are more than 156 home loans with rates below 5.2 per cent, including Yellow Brick Road's rate smasher home loan, at 3.91 per cent, and CUA, Mortgage House and Bank of Queensland's offerings, at 3.99 per cent.

Anne Fagredine, an administration officer from Picnic Point, and her husband refinanced their home loan in June, switching away from Commonwealth Bank and saving about $300 a month.

She said the extra money helped ease the burden of paying for their three young children's extracurricular activities, including sports and dancing.

"The process was easier than expected. We just asked them, applied, they did their evaluation and said yes. My husband further negotiated for a better rate," she said. "Whatever headache in the paperwork involved was more than compensated by the extra money."

Despite the prospect of big savings, the survey of more than 1300 Australians found only 6 per cent were considering switching lenders and 20 per cent had switched for a better deal in the past half decade.

Among those who have not switched, 24 per cent admitted they could not be bothered with the paperwork, 13 per cent said they thought it would cost too much, and 9 per cent said it was too hard to compare.

"The real concern is that people may be getting complacent and wasting money just by staying put. For instance, with 24 per cent of borrowers surveyed saying they couldn't find the time to fill out paperwork, isn't a form worth the time if it will mean over $8000 in savings?" said Ms Hassan.

Generation Y mortgage holders, those between 18 and 34 years of age, were more likely to have switched than any other age group. Baby boomers were the most loyal to their lender.

Tasmanians were the least likely to have switched home loans, while Victorians were the most likely.

About 63 per cent of NSW and Western Australian mortgage holders said they had never changed lenders. In these states, 18 per cent said they had switched over five years ago but stuck with the same lender since.

Millions of big bank mortgage customers started paying more interest on Friday, as variable interest rate hikes announced last month came into effect, despite the Reserve Bank keeping the cash rate at 2 per cent.

Banks blamed the increases on higher regulatory costs, but are still competing aggressively for new borrowers or those who are refinancing.

Satisfaction levels of Big Four home loan customers have declined, according to the latest Roy Morgan Research figures. ANZ experienced the biggest drop, with levels falling to 75.8 per cent, followed by NAB, Westpac and Commonwealth Bank.

Among the 11 major home loan banks, ING Direct scored the highest satisfaction levels – at 94.7 per cent – followed by ME Bank, BankSA and Suncorp.

"Only the coming months will tell us how these heavily publicised interest rate rises have affected satisfaction," said Roy Morgan Research's Norman Morris.

"Competition in the home loan market is likely to remain strong and the higher satisfaction with the smaller banks presents a major challenge, particularly as any adverse publicity regarding rate increases is generally focused on the big four banks."