Its annual survey, of 1,018 schemes run by 280 private sector firms, found that only 13% were still open to new joiners, down from 19% in 2011.
Meanwhile 31% were now closed to existing staff as well, up from 23% the previous year.
The NAPF said new staff in the private sector now had “next to no chance” of joining a final-salary scheme.
Joanne Segars, chief executive of the NAPF, said: “The pressures on final salary pensions have proven too great for many businesses. The growing liabilities fuelled by quantitative easing will have been a factor behind the record hike in closures.”
“What was once the norm is now a very rare offer. And those who are currently saving into one may find it gets closed,” she added.
Hardly any firms in the FTSE 100 now offer final-salary pensions to new recruits.
A year ago staff at Unilever took the unusual step, for the private sector, of staging several days of strikes against the proposed closure of their final-salary scheme.
The NAPF repeated its criticism of the government policy of quantitative easing (QE), which started nearly four years ago and which has helped push many final-salary schemes into large deficits.
This policy has seen the Bank of England pick up a third of all UK government bonds, in an attempt to inject cheap cash into the banking system and stave off an even deeper economic recession.
That process has raised the price of those bonds and simultaneously reduced the return they provide to investors.
And the knock-on effect has been that pension schemes need an even bigger stock of assets than before, to provide the same flow of cash in the future to pay their pensioners.
“The NAPF believes the higher liabilities created by quantitative easing and low gilt yields have prompted a barrage of fresh closures,” the NAPF said.
