A steady stream of searches ask for a Scottish child maintenance calculator, a Northern Ireland CSA calculator, or a Welsh one. Behind those searches is a reasonable assumption: family law is devolved in several respects, so surely the maintenance rules differ too.
The answer is more interesting than a simple yes or no. The calculation formula is identical across the whole United Kingdom. But the body administering it is not the same everywhere, and the surrounding law, particularly around court powers and who can apply, genuinely does differ.
What is identical everywhere in the UK
Child support is a reserved matter, not a devolved one, and the same statutory formula applies from Cornwall to Shetland to County Fermanagh:
- The percentage rates. 12 per cent of gross weekly income for one child, 16 per cent for two, 19 per cent for three or more, on income between £200 and £800 a week.
- The income bands. Nil rate, flat rate, reduced rate, basic rate and basic plus, with the same thresholds throughout.
- The £3,000 a week ceiling above which the service cannot assess and a court top up may be needed.
- The shared care reductions under Regulation 50, using the same bands of 52, 104, 156 and 175 nights a year.
- The relevant other children deduction of 11, 14 and 16 per cent.
- Pension contribution treatment and the variation grounds for unearned income and diversion of income.
- The age rules, covering children under 16, or under 20 in approved full time non advanced education or approved training.
This is why a single UK wide calculator works. Our net pay calculator produces the correct figure whether you are in Cardiff, Glasgow, Manchester or Belfast, because the arithmetic does not change.
Wales
There is no separate Welsh child maintenance system and no Welsh specific rule to know about. Wales is served by the same Child Maintenance Service as England, using the same application process, the same telephone service and the same enforcement powers.
The only practical differences are administrative. Welsh language services are available from the CMS, and correspondence can be requested in Welsh. Enforcement through the courts uses the courts of England and Wales, which is a single jurisdiction.
If you have searched for a Welsh child maintenance calculator, the standard UK one is the right one.
Scotland
Scotland uses the same CMS and the same formula, but Scots law is a separate legal system and that produces several real differences worth knowing about.
1. A child aged 12 or over can apply themselves
This is the most significant Scotland only rule, and almost nobody knows about it.
In Scotland, a child aged 12 or over can apply to the CMS for a maintenance calculation in their own right. In England and Wales only a parent or person with care can apply. The rule flows from Scots law on the legal capacity of young people, and it means a 14 year old in Aberdeen has a route that a 14 year old in Newcastle does not.
In practice it is used rarely, but it matters in situations where the resident parent will not or cannot apply, for example where they fear the other parent's reaction.
2. Aliment: the Scottish court equivalent
Where England and Wales talk about maintenance orders under the Matrimonial Causes Act, Scotland has aliment under the Family Law (Scotland) Act 1985. Aliment is the obligation to provide financial support, and it can be sought through the sheriff court.
The CMS takes priority for ordinary child maintenance in Scotland just as elsewhere, so aliment does not replace it. But aliment remains relevant in the situations where the CMS has no jurisdiction, and the Scottish courts approach those questions using Scottish statutory tests rather than the English ones.
Two points about aliment that differ meaningfully from the position in England and Wales:
- An action for aliment can be brought by a child aged 18 to 24 who is undergoing education or training, in their own name. There is no equivalent free standing route in England and Wales outside of specific circumstances.
- Aliment can in principle be sought from a person who accepted a child as a child of the family, which can extend beyond biological parents.
3. Enforcement uses Scottish procedure
The CMS's administrative powers are the same. A Deduction from Earnings Order works identically against a Scottish employer.
Court based enforcement is where it changes. In Scotland the CMS applies to the sheriff court rather than the magistrates court, and enforcement is carried out by sheriff officers rather than the enforcement agents used in England and Wales. The Scottish equivalents of the main enforcement tools are:
| England and Wales | Scotland |
|---|---|
| Liability order from magistrates court | Liability order from the sheriff court |
| Enforcement agents seizing goods | Sheriff officers carrying out an attachment |
| Charging order over property | Inhibition over heritable property |
| Third party debt order | Arrestment, including bank arrestment |
The powers achieve similar things by different procedural routes. Timescales are broadly comparable. Our guide to CMS liability orders covers the substance of what these powers allow.
4. Court orders and the one year rule
The rule that a court order for child maintenance blocks a CMS application for its first year applies in Scotland as elsewhere, including to Scottish minutes of agreement registered for execution. A registered minute of agreement is a common way for separating couples in Scotland to record financial arrangements, and it can have the same blocking effect. If you have one, check its date before applying.
Northern Ireland
This is the one place where the answer to "is it different?" is genuinely yes at an administrative level.
Northern Ireland has its own Child Maintenance Service run by the Department for Communities, not by the Department for Work and Pensions. It operates under separate Northern Ireland legislation, principally the Child Support (Northern Ireland) Order 1991 and the corresponding Northern Ireland regulations.
What is the same
Almost all of the substance. The Northern Ireland legislation deliberately mirrors the Great Britain provisions. The percentages, the income bands, the shared care reductions, the variation grounds and the enforcement powers are equivalent. A calculator built for Great Britain gives the correct figure for Northern Ireland.
What is different
| England, Scotland and Wales | Northern Ireland | |
|---|---|---|
| Responsible department | Department for Work and Pensions | Department for Communities |
| Where to apply | GOV.UK | nidirect.gov.uk |
| Contact number | 0800 171 2345 | Separate Northern Ireland number, listed on nidirect |
| Governing legislation | Child Support Act 1991 | Child Support (Northern Ireland) Order 1991 |
| Appeals | First tier Tribunal, Social Entitlement Chamber | Appeals Service Northern Ireland |
| Complaints escalation | Independent Case Examiner | NI Public Services Ombudsman |
| Court enforcement | Magistrates or sheriff court | Northern Ireland courts |
What happens when parents live in different parts of the UK
This comes up frequently and is simpler than people fear.
Great Britain, meaning England, Scotland and Wales, is a single administrative area for CMS purposes. A paying parent in Glasgow and a receiving parent in Bristol are one ordinary CMS case with no cross border complication.
Where one parent is in Northern Ireland and the other in Great Britain, there are two separate services, and there are reciprocal arrangements between them so a case can still proceed. Apply through the service covering where the person with care lives, and they will co-ordinate with the other. It adds administrative steps and usually time, but it works.
If one parent is in the Republic of Ireland, or anywhere else outside the UK, this stops being a devolution question and becomes an international one. The CMS generally has no jurisdiction over a parent habitually resident abroad, with limited exceptions such as certain Crown servants and members of the armed forces. That is covered in our guide to child maintenance when a parent lives or works abroad.
Backdating and arrears across the UK
The rules are the same everywhere. Liability generally starts from the effective date, which is normally around the date of application, and the service cannot usually create liability for a period before that. Arrears that have accrued under an existing liability have no time limit anywhere in the UK.
So the answer to whether child maintenance can be backdated in Scotland is the same as the answer for England: only in the limited sense described in our guide to backdated child maintenance. The separate question of historic unpaid amounts is covered in our guide to CMS arrears time limits.
Which calculator should I use?
The same one, wherever you are. Because the formula is UK wide, a single calculator serves all four nations. What differs is where you apply and which body handles a dispute, not the arithmetic.
Our net pay child maintenance calculator lets you enter take home pay rather than gross, which is how most people think about their wages. It applies the standard statutory formula and works equally for Scotland, Wales, England and Northern Ireland.