Tax and room rentals in Switzerland: How to declare your rental income in 2026

Faced with the housing shortage affecting many Swiss towns, taking in a tenant has become an essential solution. At Roomlala, we see every day how this practice creates social bonds while providing a useful supplementary income. However, when it comes to approaching the taxation of renting out a room in Switzerland, many hosts hesitate, fearing administrative complexity. Rest assured: renting out part of your primary residence is a 100% legal process and even encouraged by the authorities, provided you demonstrate tax transparency.

In this year 2026, the Swiss tax landscape is going through a fascinating period of transition. Between the old rules still in force and the reforms recently voted through, it is crucial to clearly understand your obligations. How can you successfully file your rental income tax return in 2026? What is the impact on your rental value? What deductions are authorised by the Federal Tax Administration? We guide you step by step so that you can rent out your room with peace of mind.

Read also: Student accommodation in Flanders: Everything you need to know about the student lease for the 2026 academic year, Autumn 2026 in Italy: The benefits of Canone Concordato for renting out your room and Regulation of seasonal rentals: What's changing for students in Spain for the start of the 2026 academic year

Understanding the legal and tax framework for homestays in 2026

Welcoming a student or a young professional into an empty room in your house or apartment is not just a gesture of solidarity, it is also an activity regulated by law. The legislation on renting out a room in Switzerland is very clear on this: any income generated from renting out a property, even partially, constitutes taxable income. At Roomlala, we make it a point of honour to support you in understanding these rules to ensure a smooth experience.

In Switzerland, the basic principle of housing taxation is based on contributory capacity. If you receive rent every month, this increases your total income. It is therefore imperative to declare these amounts to the tax administration of your canton. Failing to do so would expose you to unnecessary tax adjustments, especially since the authorised deductions often make the operation very advantageous.

It is also important to remember that renting out a furnished room in a homestay benefits from great contractual flexibility. You remain the master of your home. However, in tax terms, the Federal Tax Administration (FTA) does not make a fundamental distinction between a large apartment rented to a third party and a room rented in your own home: income must be declared precisely.

To illustrate this, let's take a common use case on our platform: you decide to rent a 15 m² room to a student at the University of Lausanne for 800 CHF per month, charges included. Over a full year, this represents a gross income of 9,600 CHF. It is this exact amount that must appear in the section dedicated to property income on your 2026 tax return.

The 2026 rental income tax return: a transparency obligation

Filling out your tax return can sometimes seem tedious, but cantonal forms have been greatly simplified in recent years. The 2026 rental income tax return is generally completed in the section reserved for income from real estate assets. You must indicate the total amount of rent received during the past calendar year.

It is crucial to differentiate the net rent from charges (water, electricity, internet). If you rent "all charges included", as is often the case for a homestay, part of what you receive is used to cover the tenant's actual consumption costs. Depending on the canton, you may be able to deduct these ancillary costs from the gross taxable income, provided that you can justify them or apply a recognised flat rate.

At Roomlala, we advise you to keep a small, accurate record of your receipts. Keep the rental agreements generated on our platform as well as proof of bank transfers. This transparency is your best ally in the event of questions from the cantonal tax authorities.

Finally, do not forget that this obligation to declare applies from the first franc received. There is no "tolerance threshold" or exemption for small amounts in Switzerland. Rigour is required, but as we shall see, it comes with very interesting rights to deductions.

Rental value in Switzerland: what is changing (and what is staying the same) in 2026

The rental value in Switzerland is arguably the most debated tax concept in the country. As a reminder, this is a fictitious income that owners occupying their own home must add to their taxable income. The idea is to create tax equity between tenants (who cannot deduct their rent) and owners (who can deduct their mortgage interest and maintenance costs).

But what happens when you rent out part of this primary residence? This is where the system requires special attention to avoid any tax injustice. In 2026, the adjustment rules are of capital importance for Roomlala hosts.

The reform calendar: no need to panic before 2029

You have probably heard about the historic vote in September 2025 enacting the abolition of the rental value. This is excellent news for owners, but pay attention to the calendar! The Federal Council has set the entry into force of this major reform for 1 January 2029. Consequently, the current tax system remains fully applicable in 2026, 2027 and 2028.

Therefore, you should definitely not anticipate the end of the rental value in your current declaration. You must continue to declare it. The good news is that during this transition period until the end of 2028 inclusive, all the advantages linked to deductions (notably the interest on your mortgage debt) are fully maintained. It is therefore the ideal time to optimise your taxation while hosting a tenant.

We wish to reassure our community: this transition period has been designed to allow you time to adapt. At Roomlala, we follow these legal developments closely to provide you with up-to-date and secure information.

Avoiding double taxation: the pro-rata adjustment

This is the question all owners ask us: "If I declare the rent for the room, and I also declare the rental value of my entire house, won't I be paying tax twice on this same room?" The answer is no, the tax administration has provided a mechanism to avoid this double taxation.

Since the actual rent for the room is already taxed, you have the right to adjust or reduce the overall rental value of your property in proportion to the surface area rented. This pro-rata calculation is essential for optimising your declaration.

Let's take a concrete example: you own a 100 m² house with an annual rental value set at 15,000 CHF. You decide to rent a 20 m² room (i.e. 20% of the total surface area) on Roomlala. You will declare the rent received for this room, but in return, you will be able to reduce your rental value by 20%. You will therefore only declare 12,000 CHF in rental value.

However, be careful with cantonal specifics: some cantons require you to fill in a specific annex to justify this calculation, while others include a dedicated box in their declaration software. Check with your local tax office to find out the exact procedure to follow.

Authorised tax deductions: optimise your return in 2026

If renting out a room generates taxable income, it also gives you the right to important tax deductions. The Federal Tax Administration acknowledges that maintaining a property in a rental condition incurs costs. In 2026, these deductions remain a powerful lever for reducing your overall tax burden.

It is fundamental to understand how to link these deductions with your rental income and your residual rental value. You generally have a choice between two methods: the deduction of actual costs or the application of a flat-rate deduction.

Maintenance costs: actual or flat-rate?

As a landlord, even for a single room, you can deduct the maintenance costs of your home. The flat-rate method is often the simplest: it allows you to deduct a percentage (generally 10% to 20% depending on the age of the building) of the rental value and/or rental income, without having to provide supporting documents.

However, if you have carried out major work to accommodate your tenant, deducting actual costs will be much more advantageous. Work carried out to maintain value (painting, replacing a window, repairing plumbing) is considered deductible. Value-enhancing work (adding a luxurious bathroom that did not exist before) is generally not.

Example use case: Before putting your room on Roomlala, you called in a tradesperson to repaint the walls and change the flooring, for a total of 3,500 CHF. If this amount exceeds the 10% or 20% flat rate to which you are entitled, you have every interest in opting for the deduction of actual costs that year, by attaching the invoices to your declaration.

We recommend that you do a simulation every year. The choice between actual costs and a flat rate is not definitive; you can opt for one or the other for each new tax return depending on the expenses actually incurred during the calendar year.

Mortgage interest deduction maintained

As mentioned previously in the reform calendar, mortgage interest remains fully deductible from taxable income until the end of the transition period, i.e. until 31 December 2028. This is crucial information for your financial planning in 2026.

The additional income generated by renting your room on Roomlala can thus be partially or totally offset by the deduction of this interest, as well as by maintenance costs. In many cases, the real tax impact of renting out a room turns out to be minimal compared to the net financial benefit you derive from it.

It is therefore strategically very relevant to rent out a room in your primary residence during this period. You maximise the use of your property while taking full advantage of the current tax ecosystem before the major shift of 2029.

Cantonal specifics and best practices for renting with peace of mind

Switzerland is a federalist country, and taxation is no exception to the rule. While the general framework described above is set by the Confederation (direct federal tax), the exact calculation of rental value, tax rates, and the exact percentages for flat-rate deductions vary considerably from one canton to another.

For example, the tax authorities in the cantons of Vaud, Geneva, or Zurich do not have exactly the same property valuation scales. It is therefore essential to insist on these cantonal specifics: what is true in Lausanne is not necessarily true to the last franc in Winterthur.

To rent with peace of mind with Roomlala, here is a list of best practices to adopt in 2026:

• Consult your canton's guidelines: Visit your cantonal tax administration website to download the 2026 explanatory notice regarding housing taxation.
• Formalise the rental: Use Roomlala's messaging and booking tools to keep a clear written record of rental dates and amounts received.
• Separate charges: If possible, clearly stipulate in your communications the part of the rent that corresponds to charges (heating, electricity), as some cantons allow these to be deducted differently.
• Anticipate the pro-rata: Precisely measure the surface area of the rented room compared to the total living space of your home to easily calculate the reduction in your rental value.

In conclusion, taxation should not be a deterrent to your desire to take in a tenant. The legal framework in Switzerland in 2026 is designed to be fair and to encourage the optimisation of living space. At Roomlala, we are proud to offer you a secure platform that facilitates these human and financial exchanges. By correctly declaring your income and applying the deductions to which you are entitled, you will make renting out your room an experience that is as personally rewarding as it is financially.