Couples could boost their retirement fund by £410,000, simply by making the most of state pension and private pension tax rules, analysis shows.

It is possible for couples to increase their long-term savings by hundreds of thousands while only having to make small amounts of extra contributions, according to interactive investor.

The investment platform found that an additional state pension of £201,500 in retirement combined with an additional private pension wealth of £208,400 would only cost couples £35,000 in extra contributions.

Here’s how couples can boost their retirement savings:

• Stay-at-home parents could boost their state pension income by £201,500 by maximising their national insurance credits over the first 12 years of their child’s life.
  
  Stay-at-home parents could miss out on 12 years’ worth of state pension entitlement if they don’t claim child benefit, losing £201,500 income over a 20-year retirement for someone currently aged 30 – assuming the state pension goes up by 2.5 per cent a year, as it currently has to under the triple lock.
  
  To receive a full state pension, retirees need 35 qualifying years. Stay at home parents can receive national insurance credits as a non-earner as long as they claim child benefit and their youngest child is under 12 years old.
  
  If they are a non-earning parent, it’s worth doing this, even if they will actually lose some or all of their child benefit due to the high income child benefit charge, just to get the credits.
  
• Non-earners could boost their retirement wealth by £208,400 if their partner pays into a private pension for 12 years on their behalf, £42,000 due to tax relief received – they would need to contribute £240 each month, which would be topped up to £300 after tax relief.
  
  Non-earners can pay up to £2,880 each year into a pension, which will be boosted to £3,600 by 20 per cent tax relief, even though they’re not earning.
  
  Over 12 years, paying into a pension for a non-earning partner aged 30, would boost their pension wealth by £208,400 by the time they reach retirement age of 68, assuming 5 per cent investment growth net of fees. The “free” tax relief element of this pension adds up to £42,000 by retirement age.

Alice Guy, head of pension and savings at interactive investor, said that planning finances as a couple is “vital” especially when it comes to long-term wealth.

This is because once couples have children, there’s often a big earnings gap for women which can have a knock-on impact on pension wealth.

She said: “The knotty child benefit rules mean that partners of high earners may be tempted to not apply for child benefit, because they will need to pay it back through the high income child benefit charge. But that decision could have a devastating impact on their state pension later on.

“Stay-at-home parents could boost their state pension income by an amazing £200,000 by the time they reach retirement age by claiming child benefit.

“That’s because non earners get national insurance credits if their children are under 12, which count towards their state pension entitlement, if they claim child benefit. The whole £200,000 is free so claiming child benefit is a no-brainer, even if it comes with some extra hassle.”