Office at home: how the self-employed lawyer deducts their home's utilities
For the lawyer who works from a room at home, since 2018 the income tax law allows deducting part of the home's utilities under a fixed rule: 30% of the proportion of square metres devoted to the activity. We explain how it is calculated.
Not every lawyer who practises on their own account rents an office. Those who work from their own home can deduct part of the home's costs in income tax. The rule was introduced by Law 6/2017 of 24 October on Urgent Reforms of Self-Employment, which added new letters to rule 5 of Article 30.2 of the Income Tax Law with effect from 1 January 2018, as the Tax Agency explains.
Which utilities can be deducted
According to the Tax Agency, when the taxpayer partly allocates their main home to carrying out the economic activity, the costs of that home's utilities are deductible, meaning:
- Water.
- Gas.
- Electricity.
- Telephony.
- Internet.
How it is calculated
The rule is fixed: 30% is applied to the proportion between the square metres of the home used for the activity and its total area, unless a higher or lower percentage is proved.
An example
| Data | Value |
|---|---|
| Total area of the home | 100 m² |
| Area used for the office | 15 m² |
| Proportion allocated | 15% |
| Deductible percentage of utilities (30% × 15%) | 4.5% |
| Annual electricity bill | €1,000 |
| Deductible electricity amount | €45 |
The example shows that the deduction is modest. Its interest lies in applying it consistently to all utilities and every year. If in the same home annual utilities added up to €2,400 across water, gas, electricity, phone and internet, the deductible amount under the general rule would be €108 (4.5% of 2,400). The figure is not large, but it adds up each year and only requires organising the invoices.
Proving a different percentage
The rule allows proving a higher or lower percentage. Anyone wanting to deduct more must be able to show greater consumption by the activity than the general rule produces. It is wise to be prudent and to document any different calculation well.
Allocating part of the home
The rule assumes part of the home is allocated to the activity. For a lawyer, that means an identifiable space devoted to work, with measurable square metres. It is advisable that it be consistent with what has been declared to the Tax Agency about where the activity is carried out.
Meal expenses
The same reform regulated the taxpayer's own meal expenses under direct estimation. According to the Tax Agency, they are deductible if they:
- Are incurred in carrying out the economic activity.
- Are made in restaurants and hospitality establishments.
- Are paid by any electronic means of payment.
They are capped at the amounts set by regulation for per diems, to which the rule refers. For a lawyer who travels to trials outside their town, it is a relevant expense, but it requires paying by card or electronic means and keeping the receipt.
How it fits with other expenses
If you are taxed under simplified direct estimation, the percentage for hard-to-document expenses is added to utilities and other documented expenses, as we explain in the guide to simplified direct estimation. And in VAT, the deduction of input tax follows its own rules, which we review in the guide to VAT for self-employed lawyers.
Checklist
- Measure the total area of the home and the area used as the office.
- Calculate the proportion and apply 30%.
- Gather the invoices for the home's water, gas, electricity, telephony and internet.
- Enter the expense in the expense record book, as we explain in the guide to the record books of the self-employed lawyer.
- Pay for meals by card and keep the receipts.
More guides in Solo and small-firm lawyers.
Fuentes
- Agencia Tributaria. Principales novedades tributarias introducidas en la Ley 6/2017, de Reformas Urgentes del Trabajo Autónomo. Accessed 18 October 2026.
The specific data in this article come from the official sources cited.
