Home Office Tax Deduction for Self-Employed UK 2026

Can the self-employed claim home office costs?

Yes. If you are self-employed (sole trader or partner) and use part of your home for your business, you can claim a deduction against your profits for the business use of your home. This reduces your taxable profit and your income tax and National Insurance bill.

The deduction is justified by HMRC's general rule that business expenses must be incurred "wholly and exclusively" for the purposes of the business. Home costs are mixed-use (personal and business), so only the business proportion is deductible.

There are two methods: the simplified expenses flat rate and the actual costs method. You choose one method for each property and must stick to it consistently. You cannot swap between methods year to year for the same home.

Method 1: Simplified expenses flat rate

The simplified expenses method uses a fixed monthly amount based on the number of hours you work from home each month. You do not need receipts or calculations -- just a record of your hours.

You cannot claim using the flat rate if you work from home for fewer than 25 hours per month.

What the flat rate covers

The flat rate covers a proportion of:

• Gas and electricity.
• Heating and lighting.
• A proportionate element of council tax.
• Cleaning costs directly attributable to your workspace.

What the flat rate does NOT cover

• Broadband and internet (claim separately as a standalone business expense, proportioned for personal vs business use).
• Business phone calls (claim separately, proportioned for personal vs business).
• Business-specific furniture or equipment (claim as capital allowances or annual investment allowance separately).
• Rent or mortgage interest (not covered by the flat rate -- if you want to claim these, use the actual costs method).

Advantages of the flat rate

• No records of actual utility costs needed.
• Eliminates the CGT risk (see below).
• Simple to apply on Self Assessment.
• Can be combined with separate claims for broadband and phone.

Method 2: Actual costs

Under the actual costs method, you calculate the proportion of your home's running costs that relate to business use and claim that proportion.

Step 1: identify your home costs

Typical home costs that can be proportioned:

• Rent (if renting) or mortgage interest (if owner-occupier -- not the capital repayment).
• Gas and electricity.
• Council tax.
• Water rates.
• Home insurance (building and contents -- business proportion).
• Broadband and telephone (business proportion).
• Cleaning.

What you cannot claim:

• Mortgage capital repayments (these are not an expense -- they build equity).
• The full mortgage interest if the room is only partly used for business.

Step 2: calculate the business proportion

The most common approach is to divide by the number of rooms used for business purposes:

Business proportion = number of rooms used exclusively for business / total rooms in the home

Alternatively, you can use floor area as the basis -- this can be more accurate if the business room is unusually large or small.

Example: A sole trader has a 5-room home (3 bedrooms, living room, kitchen). One bedroom is used as a home office. The business proportion is 1/5 = 20%.

Step 3: apply a time-use adjustment

If the room is not used exclusively for business -- for example it is a spare bedroom used sometimes as an office and sometimes by guests -- you must further adjust for the proportion of time it is in business use.

Example: The spare bedroom is used as an office 40% of the time (weekdays, during working hours). Business proportion: 20% (room fraction) x 40% (time fraction) = 8%.

Worked example: actual costs method

A self-employed graphic designer works from a dedicated home office (1 of 5 rooms, used exclusively for business):

At a 40% higher-rate tax position (income tax 40% + Class 4 NI 2%), the deduction saves approximately £3,000 x 42% = £1,260 per year in tax.

Using the flat rate (say 101+ hours per month at £26 x 12 = £312 per year), the saving would be only £312 x 42% = £131 per year -- significantly less.

The actual costs method is generally better for high-earners with significant home costs, or for those working full-time from home.

The CGT risk -- the "exclusive use" trap

If you dedicate a room exclusively to business use, HMRC treats that portion of your home as non-residential. When you sell your home, the main residence exemption (Private Residence Relief, or PRR) normally exempts the entire gain from Capital Gains Tax. But if a portion of the home was exclusively used for business and not for residential purposes, that portion may not qualify for PRR.

Example: A sole trader has a £500,000 gain on selling their home. 20% of the home was a dedicated, exclusive office. The gain attributable to the office: £100,000. This £100,000 may be subject to CGT (at 18% or 24% depending on circumstances).

How to avoid the CGT risk

The simplest approach is to ensure that business rooms are also used personally -- they remain "mixed use" rather than exclusive. A home office that doubles as a guest room, library, or general study is less likely to lose PRR.

Using the flat rate method (which does not allocate specific rooms to business use) completely eliminates the CGT risk.

HMRC guidance acknowledges that in most cases of reasonable working-from-home, there will be no CGT implication. The risk is greatest where a room is physically set up purely as a commercial workspace with no domestic use whatsoever.

Employee working from home relief

Employees working from home are not covered by the self-employed flat rate rules. Instead, employees can claim:

HMRC flat rate: £6 per week (£312 per year)

HMRC allows employees to claim £6 per week (£312 per year) without receipts to cover additional household costs. This is a relief against income tax -- not a cash payment. For a 20% taxpayer it saves £62.40 per year; for a 40% taxpayer, £124.80 per year.

This can be claimed via:

• Employer: the employer can pay £6/week tax-free as part of a homeworking allowance.
• Form P87: if the employer does not pay the allowance, the employee can claim relief via P87 (if total expenses are under £2,500) or Self Assessment.

Actual costs (employee)

Employees can also claim actual additional household costs incurred wholly, exclusively, and necessarily because of working from home. This requires records of the additional costs (e.g. increased electricity bills) and a clear link to the business requirement to work from home.

HMRC takes a narrow view: they expect the work to be required by the employer, not merely convenient. Employees choosing to work from home when an office is available may not qualify for actual cost claims above the flat rate.

Sources

• HMRC: Simplified expenses for self-employed
• HMRC: Business expenses -- use of home
• HMRC: Employees working from home
• HMRC: Private Residence Relief