Pensions company Royal London estimates that over three million people are currently missing out on a free pension contribution from their employer, one which could add a handy additional £650 to their annual income in retirement

According to Royal London, many employers offer a “matching deal” on the pensions they offer staff. Should you choose to pay in more than the minimum level, the company will then match your contributions pound for pound.

Amongst the many companies offering the “buy one get one free deal” are Vodafone, Next, BAE Systems, Tesco and Royal Mail. With some 3.2 million people currently failing to take up this offer, additional contributions of £2bn are being lost.

Under rules introduced in 2012, larger companies must pay 1% of your salary into a scheme, while employees have to contribute a further 0.8%. However, many schemes will go further and will match your contributions should you opt to pay in more.

For someone on the UK average income of £27,000 and adding contributions to their pension, this free boost would ultimately equate to an extra £650 a year.

You can find out how your income in retirement will match up to your plans by using the RetireEasy LifePlan.