Key points at a glance
- As a self-employed person, you can deduct the business share of your housing costs as a business expense under the Federal Act on Direct Federal Taxation (Art. 27 para. 1 DBG, in German).
- The room must actually be used for business. If you also use it privately, only part of the cost is deductible.
- Your calculation of the share must be easy to follow - usually by floor area or number of rooms - and backed up with your lease, utility statements and a floor plan.
- Stricter rules apply to employees: a home office is only deductible if the employer doesn't provide a suitable workplace.
When is the home office deductible?
Self-employed people may deduct all costs that are justified for business or professional reasons (Art. 27 para. 1 DBG; the cantons apply the same rule). This includes an office in your own home if it is actually used for the business. In 2005, for example, the Basel-Stadt Tax Appeals Commission accepted the rent for one and a half rooms of a sole proprietor's 4½-room apartment as a business expense.
Three points are important:
- Actual business use: You work in this room regularly - not just occasionally at the kitchen table.
- Ideally a separate room: If the room is also used privately, for example as a guest room, only part of the costs is deductible. The kitchen, bathroom and hallway generally don't count, because private use predominates there.
- Plausible for your business: If you already have business premises and only work from home now and then, the tax office will take a hard look at the additional deduction.
The burden of proof is on you: if you can't document the business share, the tax office may estimate it.
Calculating the share
There is no flat-rate deduction for a home office for the self-employed. What you need is a calculation the tax office can follow. Splitting by floor area works well: office area divided by living area. Some tax offices also calculate by number of rooms. If the room isn't used exclusively for business, you also reduce the share by the private-use portion.
Example: a graphic designer with an office in her rented apartment
Sandra lives in a 90 m² apartment and uses a 12 m² room as an office. The floor-area share is 12 ÷ 90 = 13.3%.
| Housing costs per year | CHF |
|---|---|
| Rent 12 × 1'900 | 22'800.00 |
| Utilities (Nebenkosten: heating, water) | 2'400.00 |
| Electricity | 900.00 |
| Total | 26'100.00 |
| Business share 13.3% | 3'480.00 |
If the room also serves as a guest room and Sandra uses it 80% for business, the share drops to 13.3% × 80% = 10.7%, i.e. CHF 2'784.
Which costs count?
- Rent - or, if you own your home, housing costs such as mortgage interest and maintenance instead. Cantonal practice varies here, especially because of the imputed rental value (Eigenmietwert). Check the calculation with your tax office or accountant (Treuhand).
- Utilities such as heating and water, as shown on your utility statement.
- Electricity and cleaning, insofar as they relate to the apartment.
- Depending on the canton, a share of your household contents insurance.
Office furniture, computer, printer, internet and phone don't belong in this calculation. They are separate business expenses that you record directly as receipts - equipment with a longer useful life as fixed assets.
Records you should keep
- Your lease or records of mortgage and maintenance costs,
- utility statement, electricity bills, insurance policy,
- a floor plan of the apartment with the office and floor areas marked,
- your calculation of the share, year by year.
These records are part of your bookkeeping and, like all receipts, must be kept for 10 years (Art. 958f of the Swiss Code of Obligations, CO). If your rent or utilities change, use each year's own figures for that year.
And as an employee?
If you are employed and also work from home, different rules apply. A home office is then only deductible as a professional expense (Art. 26 DBG) if you regularly have to do a substantial part of your work at home because your employer doesn't provide a suitable workplace, and you have a separate room for it that is mainly used for work. According to case law, working from home occasionally isn't enough. The details are up to the cantons; in many cases, the flat-rate deduction for other professional expenses is the simpler option.
How it works in Easly
In the "Home office" section, Easly calculates your share in a way anyone can follow - and keeps the supporting records right there with it:
- Enter once: living area, office area and the business-use share of the room, plus the monthly rent - or the mortgage interest share if you own your home - and the cleaning costs if you like.
- Utilities, electricity and household contents insurance per year: With your own AI account, you upload the statements, and Easly recognizes what kind of document it is and which year it applies to; multiple electricity bills for the same year are added together. Without AI, you enter the annual amounts by hand.
- The calculation: floor-area share × business-use share, applied to that year's housing costs. Each year keeps its own figures - later changes don't affect earlier years.
- Floor plan as evidence: You store the floor plan of your apartment as a PDF or image directly in the home office section.
- In the income statement: The share is included automatically as "Home office (proportional housing costs)", along with mileage and receipts.
Frequently asked questions
Is there a flat-rate home office deduction for the self-employed?
No. Self-employed people deduct the actual costs that are justified for business reasons (Art. 27 para. 1 DBG). Your share of the housing costs must be calculated in a way the tax office can follow, usually by floor area or number of rooms.
What if I also use the office privately?
Then only part of it is deductible. You reduce the floor-area share to reflect private use - for example to 80% if the room is occasionally used as a guest room.
What if I own my home?
Instead of rent, housing costs such as mortgage interest and maintenance count. How this interacts with the imputed rental value varies from canton to canton. Check the calculation with your tax office or accountant.
Can I deduct a home office as an employee?
Only under strict conditions: you must regularly do a substantial part of your work at home because your employer doesn't offer a suitable workplace, and you must have a separate room that is mainly used for work.
Information as of: see above. Sources: Federal Act on Direct Federal Taxation (Art. 26 and 27 DBG; in German), Swiss Code of Obligations (Art. 958f CO), and the case law and practice of the cantonal tax administrations, which differ in the details. This article is not a substitute for tax advice.