Can I claim working from home costs as self-employed?

Yes. From 25 hours a month at home, GOV.UK lets you claim a flat £10, £18 or £26 a month for 2026-27, or a reasonable share of your actual household bills.

Most tradespeople work on site, but the paperwork happens at home: invoices at the kitchen table, quotes in the evening, CIS statements filed in the box room. That time counts. The rules below follow GOV.UK and HMRC's Business Income Manual as checked on 16 October 2026.

Two ways to claim

You can use the flat rate (called simplified expenses) or work out a share of your actual costs. You do not have to use the flat rate, and HMRC's manual says it is optional whether or not you also use the cash basis.

The flat rate, by hours

The flat rate is based on the hours you spend working at home each month:

You add up the months. It covers household running costs such as heat, light and power, so you do not have to split your bills between home and business.

HMRC counts hours spent wholly and exclusively on three core business activities:

• providing your goods or services
• maintaining business records
• marketing and obtaining new business

For a tradesperson, that means time spent on invoices, the books, CIS statements, quotes and replying to enquiries.

The flat rate leaves out phone and internet. You can claim the business share of those separately, based on the actual bills.

A share of actual costs

The other way is to claim a fair proportion of real bills. GOV.UK lists heating, electricity, Council Tax, mortgage interest or rent, and internet and phone use. You need a reasonable method, such as the number of rooms used for business and the time spent working.

HMRC's manual draws a line between two kinds of cost:

• Running costs such as heat and light vary with use. For minor use, such as writing up records at home, the manual lets HMRC accept any reasonable estimate. Metered water is the exception: for minor use like writing up records, none of the water charge is allowable.
• Fixed costs such as Council Tax, mortgage interest, insurance and rent are only allowable in part if part of the home is set aside solely for business use for a period. A kitchen table used for invoices on a Sunday does not usually qualify.

You can also claim a fixed cost with an identifiable business share alongside the flat rate, according to HMRC's manual.

Worked example

A self-employed plumber does the books, invoices and quotes at home. In 2026-27 that comes to 30 hours a month for 9 months, and 60 hours in each of January, February and March while the year-end paperwork is done.

Flat rate: 9 months × £10 = £90, plus 3 months × £18 = £54. Total: £144.

Actual costs: the house has 5 rooms and the gas and electricity come to £2,500 for the year. The box room is the office, used for the equivalent of about 1 day a week. £2,500 ÷ 5 = £500 for the room, and £500 × 1 ÷ 7 = £71.43.

The flat rate gives about twice as much here, £144 against £71.43, and needs no bill-splitting. On either method, the plumber also claims the business share of the mobile and broadband.

What this means for you

For most tradespeople, the working-from-home claim is small: about £144 a year in the example above. It is still worth claiming, because it costs nothing but a note of your hours. The bigger claims are usually elsewhere: van, tools, materials and phone.

Pick one method for your household running costs and keep the workings. For the flat rate, that is a simple log of hours by month. For actual costs, keep the bills and a note of how you split them. Records should be kept for at least 5 years after the 31 January deadline for the tax year.

If your home is also a yard or workshop with heavy business use, the actual-cost route may give more, but the split needs to reflect the facts.

Steps to claim working from home

1. Keep a monthly log of the hours you spend on paperwork, quotes and other business work at home.
2. At the end of the tax year, apply the flat rate to each month with 25 hours or more. Our free simplified expenses calculator adds it up for you.
3. Or work out a reasonable share of your actual bills, by rooms and time, and keep the workings.
4. Claim the business share of your phone and broadband on top, from the actual bills.
5. Add the total to your expenses on your Self Assessment return, or in your Making Tax Digital records.

Our guide to expenses for tradespeople covers the rest. The free MTD check shows when Making Tax Digital starts for you, and the trades section has more.