The revelations came after the Financial Conduct Authority issued a warning to advice firms about defined benefit transfers, stating a number of firms were failing to meet regulatory standards.
Prudential informed FTAdviser that, as of January 2017, it was completing more than 800 TVAS reports a month, based on a six month average.
That compared with an average of just over 100 a month in 2014.
Pension freedoms - which gave those aged 55 plus the option for the first time to withdraw all of their retirement pot as they wished - were introduced in April 2015.
However those in defined benefit schemes have to transfer their pots into a defined contribution scheme to take advantage of the rule change.
Anyone who wants to transfer out of a defined benefit scheme must complete a TVAS report.
Stan Hughes, pension expert at Prudential, described the increase in demand as "quite staggering", adding that November last year saw a particularly dramatic spike.
"In the year of the 2014 budget when pension freedoms were first announced, we were running around 120 TVAS reports a month," he said.
"In November last year, we did 1,049 in one month."
A TVAS report calculates the "critical yield" needed from a personal pension to match the guaranteed income DB scheme members are giving up.
However, not everyone who has a TVAS report prepared goes through with the transfer.
In addition to the inheritance tax advantages allowed by pension freedoms - where if the fund holder dies before age 75 a beneficiary can inherit some or all of the fund as a lump sum, or income from drawdown, tax free, up to the lifetime allowance of £1.25m - Mr Hughes said demand was being driven by record high transfer values.
He said he had recently seen a transfer value that was 48 times the value of the annual pension.
That would mean that, if the member in question transferred out of their defined benefit scheme into a defined contribution scheme or a drawdown fund that only matched inflation, they would be able to pay themselves an equivalent income for 48 years before running out of money.
If they retired at 65, that would take them to 113-years-old.
Mr Hughes said current high transfer values - driven by ultra-low gilt yields - were extremely tempting.
"People are getting these lottery numbers thrown at them. Then they run the TVAS report and all of a sudden, the critical yield that last year they might have been unsure about has now come down significantly, and so they're thinking, 'Let's have another look at this.'"
However, he said even with multiples of 48, transferring out was not always the sensible option.
"If somebody was quite young - in their 30s or 40s - and they got a transfer value of that size, it's a long time before you can actually take the money. So you've got to make sure you don't lose it.
"Imagine transferring out in 2008 and losing 20 per cent of your pot on day one because you just happened to get the timing wrong," he said, adding it was key for the adviser to ascertain the clients' objectives and their attitude to risk.
Last week, the Financial Conduct Authority warned that some financial advisers were not meeting regulatory standards on defined benefit transfer advice.
The regulator stated a number of firms were basing their recommendations "solely on whether or not the critical yield is below a certain rate set by the firm for assessing transfers generally", rather than comparing it to the specific investments the client intended to take up.
The FCA said this did not meet its expectations.
FTAdviser contacted a number of other TVAS report providers, and all reported similar spikes in demand.
Old Mutual Wealth, also a major provider of TVAS reports, revealed it had seen demand increase sixfold over the last two years.
Jon Greer, a pensions technical expert with the firm, said transfer values had also risen considerably, saying it was now "not uncommon to see multiples of 30 – 35 times the notional annual value of DB benefits".
Intelligent Pensions, meanwhile, told FTAdviser it had gone from doing "one or two" TVAS reports a month, to doing 40 to 50.
The firm's marketing director Andrew Pennie said demand was still growing, adding that he had seen some transfers with income multiples "in the 40’s".
However, he said 25 to 30 times was "more typical".
james.fernyhough@ft.com
