The new Class 3A state pension top-up scheme is available to everyone who is already entitled to state pension or will be before 6 April 2016.

That is all men born before 6 April 1951 and all women born before 6 April 1953.

The deal opened on 12 October and will last until 5 April 2017. You can buy the extra pension at once or in stages.

If you change your mind you can get your money back and give up the extra pension within 90 days of paying.

The top-up can be bought in units of £1 a week up to a maximum of £25 a week, or £1,300 a year. The purchase cost depends on age.

Malcolm McLean, senior consultant at Barnett Waddingham, says that at age 65, an extra pound of pension costs £890, so for the full £25 a week you would have to shell out £22,250.

At the age of 75, he says the cost is £779 or £16,850 for the full £25 a week.

The cost may seem high, but Mr McLean says it is worth noting that the extra pension is index-linked (as measured by the CPI) and at least half can be inherited by a spouse or civil partner.

• Story (at 19th November 2015) taken from the FT Adviser website: http://www.ftadviser.com/