With careful planning, you can retain your pensions allowance

fixed term, will provide you with an income and not affect your future allowance. It needs to be a standard annuity that pays a level or rising rate of income.

Secondly, taking just your tax-free cash entitlement will preserve the normal £40,000 allowance. Everyone is entitled to take at least a quarter of their fund in this way. Once you take more, and tax is due, the reduced allowance is triggered.

Thirdly, if your pension provider or scheme allows it, the “small pots rule” can also help. This allows you to take, as cash, up to three personal pensions of less than £10,000 each. However, it requires each pot to be separate and some firms may struggle to administer the manoeuvre.

Lastly, before April 2015 you could open a “capped drawdown” account. These allow you to take an income up to a cap, which fluctuates based on interest rates. If you take too much income and break the cap you’ll lose your allowance. If you don’t have such an arrangement, you cannot set one up now.

Although the Government hasn’t mentioned it, those with final salary pensions – where income is guaranteed and based on length of service – will also see changes, warned Ms Trott.

The new £4,000 allowance applies only to defined contribution pensions, but will eat into the normal £40,000 limit that applies across all types of pension. It is expected this will mean final salary savers will have an allowance of £36,000 a year once they access their money purchase pension, although it will depend on the final rules.

David Robbins of Willis Towers Watson, the pensions consultancy, added that auto- enrolment, the requirement for all employers to contribute to a pension on behalf of their staff, might also be affected. He said people who earned £44,445 or more and made 9pc contributions would break through the new lower allowance, potentially without noticing.

But simply knowing about the reduced annual allowance is not the end of the headache that savers face. It is up to individuals to monitor their own levels of pension savings. Providers are required to tell you if your actions, such as taking regular income payments from your pot, trigger the lower allowance. But that is the end of their obligations.

If you miss the warning – and don’t reduce your contributions below £4,000 a year – no one will stop you breaching the limit and eventually facing potential penalties.

Mr Robbins said: “The onus is on individuals who access one pension flexibly to inform any other pension scheme that they are paying contributions to.

“Where people fail to do this, they could get a backdated bill for a few years’ worth of annual allowance charges.”