Prudential has reinforced its position as the strongest major provider of with-profits investments, adding £2 billion to policies last year.

Its typical Scottish Amicable Savings endowment earned a 5.8% return in 2013, while a typical Prudential endowment mortgage maturing in 2014 will have added 8% to its value in its final year.

"The payouts from Prudential compare favourably against other stronger with-profits providers such as Aviva and Legal & General and are hugely superior to the weaker providers such as Scottish Widows," sector expert Patrick Connolly of advisers Chase de Vere commented.

Prudential's 20-year £200 a month pension payout of £85,460 compares with Aviva at £84,921, Standard Life at £78,669, Legal & General at £78,544 and Scottish Widows at £70,863

Prudential's 25-year £50 a month endowment payout of £31,438 compares with Legal & General at £29,278, Aviva at £28,869, Standard Life at £27,304 and Scottish Widows at £25,842.

Some smaller closed funds can boast even better pay-outs, according to figures issued on Monday by Phoenix, whose stable includes three former Scottish life office funds. The 25-year Scottish Mutual endowment pay-out was £32,601 while the Scottish Provident policy matured at £36,739. Life Association of Scotland, however, achieved only £25,252. Most Phoenix funds have cut annual bonuses to zero though the Scottish Provident life fund paid 1.5%.

David Belsham, actuarial director at Prudential, said: "Our fund has consistently outperformed the market over the long-term and has given our customers better returns than many other investment options available."

Ned Cazalet, leading industry commentator, said: "Much of Prudential's with-profits fund investment performance has been used to enhance claim values over and above amounts contractually guaranteed. This is not always the case for some other with-profit providers who, because of onerous guarantees, are hamstrung in their ability to transmit investment returns to policyholders."

Prudential said its fund had delivered a return of 119.4% over 10 years, compared with the FTSE 100 index return of 116.6% and it continued to offer attractive annual bonus rates of 2% on the with-profits bond and personal pensions and 2.25% on corporate pensions.

Mr Connolly said: "While it is easy to be critical of with-profits investments, there are often good reasons why investors should retain existing policies. The financial strength of the product provider, their ability to invest in growth assets and their commitment to paying competitive bonuses and payouts should be important considerations. Prudential is the market leader in these respects."