Working from home: what can you deduct in the UK and Spain?
Flat rate or a reasonable proportion
Sole traders choose between HMRC's simplified flat rate (a fixed monthly amount based on hours worked from home) or a calculated share of actual costs — rent, utilities, council tax — proportioned by rooms and usage. The flat rate is less money but zero argument; the proportion is more money and more paperwork.
Declared m² — utilities at 30% of that share
Spain wants the percentage of your home used for the activity declared on your Modelo 036/037 census. Utilities (electricity, water, internet, gas) are then deductible at 30% of that declared proportion — e.g. 20% of the home affected means 30% × 20% = 6% of each bill. Rent itself is messier in practice (contract wording and landlord VAT issues), so it needs your gestor's judgement.
If you file in both countries
Both systems allow something, but they calculate it completely differently — a UK flat-rate claim has no Spanish equivalent, and Spain's 30%-of-proportion rule surprises everyone the first time. Track the underlying bills once and let each return take its own slice.
Evidence to keep
- ✓Utility bills in your name for the property
- ✓Your declared affectation percentage (from the 036/037) — keep a copy
- ✓Rental contract, if you intend to claim any rent share in Spain
Frequently asked questions
What is the 30% rule for autónomos?
If you work from home and declared part of it for your activity, utilities are deductible at 30% of that declared proportion of the bill — not 30% of the whole bill.
Do I have to tell Hacienda I work from home?
To deduct home costs, the affected square metres should appear on your census declaration (Modelo 036/037). Claiming without that declared base is asking for a rejection.
Catalejo provides software for organizing tax records and producing estimates. We are not registered tax advisors; rules change and individual circumstances differ. Treat this page as general information and confirm your own case with a gestor or accountant before filing.