Are missing NI Pension contributions worth it?

p00hsticks

molerat said:

But it doesn't really matter as with 37 pre 2016 years any year 2015-16 and earlier will not add to her pension so cannot be purchased.

Being a bit pedantic, but an important distinction..... 
any unfilled 2015-16 and earlier year CAN be purchased (at least until the July deadline) but SHOULD not as they won't add to her pension. 
HMRC will take payments for any unfilled year from 2006 onwards, but don't know what impact if any it will have on your /state Pension, which is why people are told to go the the Future Pension Cetnre first for advice on which years (if any) to buy.