Competition in the mortgage market shifted to longer-term fixed rates yesterday, when three of the big banks announced cuts to their five-year rates. Two of the lenders, Westpac and Commonwealth Bank, said they had never offered such low five-year rates before.NAB is cutting its three-year fixed rate by 11 basis points to 4.94 per cent, its four-year rate by 45 bps to 4.99 per cent and its five-year rate by 70 bps to 4.99 per cent. The rates changes are effective from Friday.NAB's is offering rates of less than five per cent for fixed terms from one to five years.CBA is cutting its five-year fixed rate by 70 bps to 4.99 per cent. The new rate applies to the bank's Wealth Package and Mortgage Advantage Package products.Westpac is cutting its five-year rate by 80 bps to 4.99 per cent. The offer includes a discount of 20 bps under the bank's Premier Advantage Package. The new rate is effective from next Monday.A recent rally in the Australian government bond market, which influences the swap rates that lenders use to hedge their fixed-rate exposures, has given the banks room to move on fixed rates.According to the comparison site Infochoice.com.au, other lenders that have cut their fixed rates in the past month include MyRate.com.au, Qantas Credit Union, Bankwest, ING Direct, Greater Building Society and Resi Home Loans.While the new rates look attractive, they may not have a big impact on sales. With the prospect of Reserve Bank monetary tightening now being pushed out to 2015, borrower demand for fixed rates has waned. Leading broker groups report that standard variable rate loans are in the ascendancy.Mortgage Choice reported earlier this month that 75.3 per cent of home loans written by its brokers in June were variable rate loans - up from a 12-month average of 72.6 per cent.Aggregator AFG reported that the proportion of standard variable rate loans sold by its brokers in June was 60.3 per cent - up from 58.2 per cent in January and 57.2 per cent in June last year.When borrowers do opt for fixed rates they tend to go for terms shorter than five years. The three-year term is usually considered the sweet spot.