Claiming Marginal Relief
HMRC is currently targeting companies that may have incorrectly claimed corporation tax marginal relief (MR). If your company falls into this category, you might receive a letter questioning your claim. So what’s going on and what should you do?
When corporation tax increased in April 2023, marginal relief was introduced to ease the jump. Companies with profits up to £50,000 pay 19%. Once profits go over that, the 25% main rate kicks in. Marginal relief softens that jump for companies with profits between £50,000 and £250,000, tapering the tax increase so it’s not such a shock.
But, if your company is associated with other companies, they must share the marginal relief limits. You don’t get separate £50,000 and £250,000 thresholds for each one!
Companies are seen as “associated” if; they’re in the same group, they’re controlled by the same people or if they’re commercially linked.These rules are tricky, and HMRC believes many businesses have misunderstood them, leading to overclaimed relief.
If HMRC thinks you may have overclaimed, it will send a letter. Some versions are quite firm and hint at compliance checks. What you must do is;
- Review your corporation tax return for the period including 1 April 2023 onwards
- Check whether the companies HMRC lists as “associated” really are associated
Don’t assume HMRC is automatically right. In some cases, its list has included passive companies that shouldn’t count towards the marginal relief calculation.
Technically, you’re not legally required to reply within 30 days. Practically? You should. Ignoring it increases the risk of a formal enquiry later. If you need more time, ask for an extension. And if you still believe your marginal relief calculation is correct, ask HMRC to explain its reasoning.
If you receive a marginal relief letter, don’t panic! Just give us a call on 01622 738165 and we can figure out if your marginal relief calculation is correct and how to move forward with HMRC










