How to Claim Home Office Expenses for Tax

The Home Office Deduction: Widely Available, Widely Missed

If you work from home - whether you're self-employed, a freelancer, a sole trader, or a business owner who works from a home office - you may be entitled to claim a proportion of your household costs as a business expense. This deduction is widely available and widely missed. Many self-employed people either don't know they can claim it, or claim it incorrectly and later face a tax authority query. Getting this right means more money in your pocket without any increased audit risk.

The rules differ slightly between the UK and other jurisdictions, so this guide covers both HMRC's approach and the general principles. Always confirm the specific rules that apply to you with your accountant or tax software.

Two Methods: Simplified vs. Actual Costs

In the UK, HMRC offers two approaches for self-employed people working from home:

Method 1: HMRC's simplified flat rate. HMRC allows a flat monthly deduction based on the number of hours you work from home per month: £10/month for 25–50 hours/month; £18/month for 51–100 hours/month; £26/month for more than 100 hours/month. This is simple, requires no complex calculation, and carries low audit risk. The trade-off is that for many people, the actual costs are higher and the simplified rate underestimates the legitimate deduction.

Method 2: Actual costs (proportional). You calculate the proportion of your home that is used for business and apply that proportion to your eligible home costs. The proportion is typically calculated as: (number of rooms used for business / total number of rooms in the home). You then apply this proportion to your annual costs for gas, electricity, water (if business-relevant), broadband, and council tax (but not rent or mortgage interest for sole traders - this creates a capital gains tax risk). This method typically yields a larger deduction but requires more detailed calculation and documentation.

What Costs Can You Include?

Under the actual costs method, eligible home office costs typically include:

• Gas and electricity (your heating and lighting costs for the home)
• Water rates (if relevant to your business activity)
• Broadband and telephone line rental (the business proportion)
• Council tax (the business proportion - note that in some areas, using a room exclusively for business can affect your council tax band, so review carefully)
• Buildings insurance (the business proportion)

Costs you generally cannot include as a sole trader: mortgage interest or capital repayments, rent payments (including these can create a capital gains tax issue by treating part of your home as a business asset).

The "Exclusive Use" Rule

For a room to qualify for the proportional home office deduction, it should be used regularly and exclusively for business. A dedicated home office that is only used for work qualifies cleanly. A kitchen table where you sometimes work qualifies for nothing - it has personal use. A spare room that doubles as a guest bedroom is a grey area. HMRC's simplified rate avoids this issue entirely - you claim based on hours worked, not room usage. The actual cost method requires you to be able to genuinely justify that the space claimed is used for business.

Keeping Records

If using the actual costs method, keep records of: your utility bills showing annual costs, the basis for your proportional calculation (number of rooms, floor area if you prefer area-based calculation), and notes on which rooms are used for business and how. If HMRC queries your claim, you should be able to demonstrate clearly how the deduction was calculated. Related reading: best practices for storing receipts and records.

Limited Companies: Different Rules

If you operate through a limited company and work from home, the company can pay you a home office allowance. HMRC allows a flat rate of £6 per week (£312/year) as a non-taxable payment from the company to you, without any documentation required. Alternatively, the company can pay a higher "use of home" charge supported by a detailed cost calculation, but this is more complex and usually only worthwhile if your actual costs are significantly higher.

How Note.now Makes This Easy

Note.now includes a home office expense calculator that helps you determine the correct deduction based on your working hours or room usage. The calculated amount is added to your expense records automatically. See also: self-employed tax guide and year-end expense review. Start your free Note.now account and claim every deduction you're entitled to.