A report about a possible Child Maintenance Service, or CMS, income rule can make it sound as though the calculation has already changed. The official position is more careful. The Department for Work and Pensions, or DWP, consulted in 2021 on including certain unearned income in the standard calculation. In its 2022 response, it said it planned to make the unearned-income regulations at a later date. The current GOV.UK guidance still describes a variation route for certain other income.
This article is general information for parents using the statutory CMS scheme in Great Britain. It is not legal or financial advice, it does not calculate maintenance, and it cannot say what should happen in an individual case. Sources were read on 17 September 2026.
The short answer: the DWP proposal would move certain unearned income from something that may be considered after a variation request into the standard calculation. The official guidance currently says a variation can be requested for specified other income and assets.
What the DWP proposed
The 2021 DWP consultation proposed that unearned income held by HMRC could be included alongside a paying parent’s earned income when the CMS first calculates maintenance. It also proposed using the approach at annual reviews. The consultation described unearned income as certain taxable income from savings and investments, land or property, or other miscellaneous sources.
The proposal was not that every asset would automatically become income. The DWP’s own language was narrower: it referred to unearned income reported to HMRC and explained that legislation would be needed before it could be included in the standard calculation.
The government response, published in 2022, said that where unearned income is identified at initial case set-up, it would be included in the paying parent’s income for the calculation. But its next-steps section also said it planned to make the unearned-income regulations at a later date. That is why it is important not to treat the proposal or the response as a new calculation rule by itself.
What the official rules say today
The current starting point for the statutory scheme is the paying parent’s gross annual income, using information from HMRC where available. The current Child Support Maintenance Calculation Regulations 2012 list employment income, pension income, specified taxable benefits and trading income in the HMRC figure used for historic income.
GOV.UK’s current page on asking for other income and expenses to be included says that either the paying or receiving parent can ask for a variation when applying for maintenance or after it has been worked out. The page lists rental income over £2,500 a year, and interest and dividends from savings and investments over £2,500 a year, among the income that can be considered.
That distinction is the useful one for now. A variation is not the same as having an income source automatically included in every standard calculation. The proposed change concerned that difference. It did not create a new rule at the point of the consultation, and this article has found no official commencement date in the sources above.
Why the proposal matters
The DWP said the purpose was to make the calculation reflect more of a paying parent’s income where HMRC holds relevant information. It also said that, under the system described in the consultation, additional unearned income was included only if either parent reported it and requested a variation.
For some parents, the change being discussed may sound straightforward. For others, it may raise questions about rental income, dividends or savings interest. Those questions are exactly why it is better to separate three things: the proposal, the current published guidance, and the facts of an individual case.
A headline cannot tell you whether a particular payment meets the current criteria, whether the CMS has the relevant information, or what effect it could have on an assessment. It also cannot tell you when, or whether, a proposal will be brought into force. Only the official rules that apply at the time, and the CMS’s decision in the case, can do that.
If you think other income may be relevant now
The current GOV.UK guidance is the right place to start, rather than a news report or an old consultation. It sets out the types of income and assets that either parent can ask the CMS to take into account through a variation. It also says that a variation can be requested at application stage or after maintenance has been worked out.
Keep the question factual. Note the income or asset type you are asking about, keep any information you already hold safely, and use the CMS route in the current guidance. Do not assume that a proposed future rule applies to an existing calculation. Equally, do not assume that the fact a rule is proposed means a variation is unavailable today.
If the issue is about the ordinary costs of raising a child between two homes, it can help to keep that separate from statutory maintenance. Our guide to child costs after separation explains the practical difference between child maintenance and shared extras such as school costs, clubs or childcare arrangements. It is also general information, not a maintenance calculation.
A calm way to read future updates
When you see a new report, ask two simple questions. Does it link to a current official announcement or regulation? And does it say when any new rule starts? If it does neither, it may be describing the 2021 proposal or 2022 response rather than a change that has taken effect.
The DWP consultation and response remain useful context. They show what was proposed and how the government said it intended to move forward. The current GOV.UK variation guidance remains the practical official source to check when a parent is deciding what route may exist now.
As of 17 September 2026, the careful description is this: the DWP proposed including certain unearned income held by HMRC in standard CMS calculations, but the current GOV.UK guidance still describes a variation route for specified other income and assets. Treat any future change as a future change until an official source says that the rules have changed and explains when they apply.