Working from home is one of the most-claimed and most-misclaimed items on a Self Assessment return. The rules are different depending on whether you are self-employed or an employee, and for employees they have changed for the current tax year. Read the section that matches your situation.
If you are self-employed
You have two ways to claim for the use of your home. You can use simplified expenses (a flat rate), or you can work out the business share of your actual household costs. Whichever you pick, the underlying rule is that the cost must be incurred wholly and exclusively for the business (ITTOIA 2005, s34), which is why a flat rate and a proportion of rent are alternatives, not additions.
Flat rates
gov.uk's page on working from home under simplified expenses sets monthly amounts by hours worked at home:
| Hours worked at home each month | Flat rate per month |
|---|---|
| 25 to 50 | £10 |
| 51 to 100 | £18 |
| 101 or more | £26 |
You can only use the flat rate if you work at least 25 hours a month from home. It covers household costs such as utility bills, so you do not need to work out a business share of those. It does not cover telephone or internet costs, which you can claim on top by working out the business share of their actual cost.
gov.uk's example: working 40 hours a month for ten months and 60 hours in two months gives 10 × £10 + 2 × £18 = £136 for the year. Working 101 hours or more every month would give 12 × £26 = £312 (our arithmetic from the same rates).
Actual costs
The alternative is to work out the business proportion of your actual costs, such as heat, light and broadband, using a fair basis like rooms and time. It takes more records, and it can come out higher if you live in a large home with heavy bills. gov.uk recommends using its simplified expenses checker to compare the flat rate with your actual costs.
Interaction with the trading allowance
If you claim the £1,000 trading allowance instead of expenses, you cannot also claim a home-office deduction on that income. Compare both before choosing.
If you are an employee
Employee relief is narrower, and the rule changed. gov.uk's guidance on tax relief for employees working at home says:
- For 6 April 2026 to 5 April 2027 you cannot claim working-from-home relief.
- You can still claim for the four previous tax years.
- You must have had to work from home, for example because your job is too far from an office or the employer has none. Working from home by choice does not qualify, even where your contract allows it.
- Eligible costs are those tied to your work, such as business phone calls and gas and electricity for the area you work in. Shared costs like rent or broadband do not qualify.
- You can claim a flat £6 a week or the exact extra amount you spent. Relief is at your tax rate, so at the 20% basic rate £6 a week gives £1.20 a week of relief. A full 52-week year at £6 a week is £312 of costs, worth £62.40 at the basic rate.
- You need evidence that you had to work from home, and receipts or bills if you claim actual costs.
If you file Self Assessment, gov.uk says you must claim through your return instead of the separate online service. For 2025/26 the claim goes in the employment expenses section of your return; see our SA102 employment guide for where it sits alongside other expenses.
Records to keep
- A log of hours worked at home each month (self-employed flat rate).
- Utility bills and the basis you used to split them (actual costs).
- Written confirmation that your employer required home working (employees).
- Bills for any telephone or internet you claim separately.
See Self Assessment record keeping for how long to keep them.
Common mistakes
- Claiming a flat rate and a proportion of the same costs.
- Claiming the employee £6 a week when working from home was a choice.
- Forgetting to claim phone and internet separately on top of the flat rate.
- Assuming the 2026/27 restriction removes the right to claim for past years, which it does not.
How ac-co helps
ac-co drafts your SA100 from your bank and books, shows the full tax computation, so you can see the effect of the expense figures you use before you approve the return for filing. Work out which method suits you first, using the gov.uk checker or your own bills.