£10,000 couple penalty shatters wedding prospects for low-income British couples 

£10,000 couple penalty shatters wedding prospects for low-income British couples 

July 6, 2026

Report finds poorer married parents are more stable than richer unmarried parents 

A single mother is nearly £10,000 a year worse off if she marries or moves in with the child’s father, because of the way the benefits system treats couples, according to new research.
 
The Stability Advantage, a new report by Dr Harry Benson published by the Centre for Social Justice (CSJ), warns of a “couple penalty” that punishes parents for choosing the best thing for their families – marriage. 
 
The couple penalty is exemplified by a mother aged 30 who is not in work and is looking after her one-year-old full-time. She would be £5,700 per year worse off if she marries or just moves in with the child’s father who earns only £20,000 per year gross (less than the minimum wage). If he earns £30,000 per year, she would be £9,600 per year worse off. 
 
The CSJ is calling for an end to this penalty by reforming the tax and benefit system. It wants to end a system that actively disincentivises formal relationships, despite the evidence that stable family relationships are associated with better outcomes for children.
 
One of the think tank’s recommendations is “to redesign financial support in the early years of parenthood, using financial incentives that shift the timing of marriage forward.”
 
Its new report reveals how, in a direct challenge to a “deeply embedded assumption in policy thinking”, “marriage itself is associated with a substantial reduction in the risk of union dissolution, even after accounting for a wide range of socio-economic and demographic factors”. 

It criticises “standard approaches” that exclude important data and thus will understate instability among unmarried parents and, in turn, understate the strength of the association between marriage and stability. 
 
Most suggest that economic advantage is the main driver of family stability, however Dr Harry Benson’s analysis of the Millennium Cohort Study has found that this is not the case. Instead, the report has found that marriage itself accounts for a substantial share of the difference in outcomes between couples who marry and those who do not. 
 
In fact, over the first fourteen years of parenthood, parents in the poorest fifth of households who marry at any point are less likely to separate (26 per cent) – even after controlling for a wide range of socio-economic and demographic characteristics – than in the richest fifth who never marry (46 per cent). 
 
Policies that are neutral on marriage are not neutral in effect. A strategy to reduce poverty that overlooks family stability will remain incomplete, the report warns.
 
Cohabiting couples are almost twice as likely to separate as married couples during the early years of their children’s lives. No matter the economic background of parents, marriage makes relationships more stable.
 
Additionally, parents on lower incomes who stay together throughout their first fourteen years of parenthood are close to twice as likely to move up income quintiles as those who separate (53 per cent compared to 29 per cent). Almost all higher earners who separate move down compared to less than half those who stay together (88 per cent compared to 45 per cent).  
 
This comes on the back of previous CSJ research that found that the number of marriages has sunk from 400,000 in 1973 to 224,402 in 2023, despite the UK population rising by over ten million from 56 to 67 million. This is the lowest number of marriages in a year since records began in the 1850s, outside of the Covid years.
 
This means marriage is down by 77 per cent for men and 73 per cent for women in just fifty years. 

The CSJ also highlights the wider economic implications of family breakdown as lone-parent households are more than ten times as likely to be long-term workless as couple-parent households.

Sophia Worringer, Deputy Research Director of the Centre for Social Justice, said:

Families should not be made poorer for making a lasting commitment to one another. Marriage is one of the clearest indicators that parents will stay together, and children benefit when they grow up in stable households.
 
‘Our welfare and tax system should reward commitment, not penalise it. If ministers are serious about reducing child poverty, supporting family stability — including marriage — must be at the heart of their strategy.”

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