Introduced following the autumn statement 2013, the Marriage Allowance lets an individual transfer £1,060 of their personal allowance to their husband, wife or civil partner, reducing the recipient’s tax bill by up to £212. To benefit as a couple, the lower earner needs to have an income of £10,600 or less and the other needs to be a basic rate taxpayer.

In its economic and fiscal outlook report prepared for the Treasury, the OBR notes that the take-up of the transferable marriage allowance has been much lower than initially assumed.

The report states: ‘We have incorporated a take-up rate of 12% for 2015-16 compared with over 70% in the original costing. We assume that take-up eventually rises to around 50% by the end of the forecast period.’

The report goes on to suggest a number of reasons why many fewer couples than predicted have opted to make use of the allowance, including IT problems for many people trying to claim it.

It states: ‘Lower take-up is likely to reflect issues with HMRC’s IT systems, a lack of awareness of the allowance (e.g. reflecting limited initial advertising) and possibly a reluctance by those eligible to engage with HMRC.’

As a result of the lower take-up rate, the Marriage Allowance has boosted receipts by £0.4bn in 2015-16, the OBR says. It calculates only 504,000 people have taken up the marriage tax break.

The OBR analysis also shows the yield from the Budget 2014 measure on voluntary NICs has been much lower than anticipated. This measure enabled pensioners to acquire additional state pension in exchange for a lump sum national insurance payment at an actuarially fair price.

Take-up has been much lower than expected, although the average amount contributed has been higher. The OBR says it now expects receipts of around £65m in both 2015-16 and 2016-17, compared with original estimates of £435m in both years.

The OBR’s economic and fiscal outlook is here