There have been suggestions that Chancellor George Osborne may reduce the amount of pension contribution allowance, which stands at £50,000, to £40,000 or even £30,000 a year.
Stewart Dick, head of sales at Hornbuckle Mitchell, said: "Those individuals who were considering maximising their pension contributions, may wish to do so now and ensure that the money is with their provider before December 5, wherever possible.
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"Those who have unused contributions from the previous three years may wish to maximise the opportunity to contribute up to £200,000 this year, as the carry forward facility might also be attacked."
John Richardson, head of retirement planning at Towry, likened the changes to a "perfect storm".
He said: "With recent changes to the industry impacting negatively on pension savers and annuities offering greater potential income than through income drawdown, there is a perfect storm creating great uncertainty over pensions.
"The need for real innovation to help individuals realise the potential value of their pension savings has never been greater."
He said there had also been speculation that enhanced drawdown rates could be introduced for people who qualify for enhanced annuities.

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