In 2029 the imputed rent tax goes. For holiday homes, a new calculation begins.

Picture this: a couple from Zurich view a holiday apartment in the Engadine on a Saturday in October. Location, layout, view, everything fits. As they leave, they ask a question no brochure answers: “What will this apartment cost us every year from 2029?” The agent says that is one for a tax adviser. True. But the couple drive home with the question, and that evening they ask Google.

The vote of 28 September 2025 is often read as a tax cut for owners. Whether it is one depends on the mortgage, on maintenance and, for second homes, on a new tax that has not been passed yet. Anyone selling a holiday home today is selling it to someone doing these sums for the first time.

What is settled for 2029.

On 28 September 2025, the Swiss people and cantons approved the federal decree on cantonal property taxes on second homes. That vote also brought into effect Parliament’s law abolishing the tax on imputed rental value, for main homes and second homes alike. On 1 April 2026 the Federal Council set the reform’s entry into force for 1 January 2029. Until the end of 2028, the current system applies.

Deductions go with the imputed rent. The deduction for maintaining an owner-occupied property ends at federal, cantonal and municipal level. Mortgage interest stays deductible only in proportion to the rented or leased property in a person’s total assets. People who buy a home in Switzerland for the first time and live in it get a temporary deduction: at first up to CHF 10,000 for married couples and CHF 5,000 for single taxpayers, for ten years, falling each year by ten percent of the maximum. For federal income tax, the deductions for energy-saving and environmental investments also disappear.

An example from the Federal Tax Administration’s fact sheet makes it concrete. Someone who owns a holiday apartment for their own use and a bank account, and pays CHF 4,000 a year in mortgage interest, will be able to deduct none of it from 2029.

What the mountain cantons are doing about it.

This is the part no brochure explains. The new constitutional provision lets cantons levy a special property tax on second homes used mainly by their owners. Each canton decides. Graubünden, home to St. Moritz and Davos, estimates its lost revenue on second homes at CHF 40.5 million a year for the canton and CHF 32.5 million for its municipalities. On 27 August 2026 the cantonal government opened a consultation. The tax would be levied on the property’s tax value, with a proposed cantonal rate of 1.5 per mille. Municipalities decide for themselves whether to introduce such a tax and at what rate.

The consultation runs until 27 November 2026. The change to the cantonal constitution goes to a mandatory referendum, and the government is aiming for entry into force on 1 January 2029. It also proposes scrapping the cantonal deductions for energy-saving and environmental measures and for demolition costs ahead of a replacement building. The deduction for work on listed buildings would stay.

A simple calculation, only to show the order of magnitude: on a tax value of CHF 2 million, the proposed cantonal rate would come to CHF 3,000 a year. What the municipality adds, nobody knows yet. This is not a tax calculation. It is the reason your buyer is asking.

The blind spot.

Between now and 2029, people will buy holiday apartments whose annual cost will only be fixed later. Municipalities decide after the canton, and each one on its own. Two identical apartments in two neighbouring municipalities may therefore cost different amounts from 2029. The price difference is in the brochure. The cost difference is nowhere.

In its Alpine Property Focus 2026, UBS expects tighter Lex Koller rules or second-home taxes to have only a limited impact on demand. That is a forecast, not a fact, but I find it plausible. If it holds, what changes is less the number of buyers than what they want to know.

The price is in the brochure. The cost from 2029 is not written anywhere yet.

Where I stand.

If I ran an agency in the mountains, I would not wait for the cantonal parliament to decide. I would write the page now that explains what is settled, what is open and when it will be decided, with dates and sources, reviewed by a tax adviser. Whoever answers first, and answers well, is the one found on the evening the couple from Zurich search. Uncertainty is no reason to stay quiet. It is the reason your buyer needs you.

What I would check.

• A page on 2029. What disappears with the imputed rent, what arrives with the second-home tax and what is still open in your canton.
• A table by municipality. Which municipalities in your area introduce a special property tax and at what rate, as soon as they decide.
• One line in each listing. A short note on the 2029 change and a link to that page, instead of silence.
• The sellers’ question. Owners who renovate before selling ask whether the timing, before or after 2029, matters. The answer belongs to a tax adviser. Your website should say that the question exists.
• The date. Every figure with its status and source, and an update as soon as the canton and municipalities decide.

Between now and 2029, step by step.

1. This week

   List the open points

   The decisions still pending in your canton and municipalities before 2029, each with its date.

2. This month

   Write the page

   What is settled and what is open, reviewed by a tax adviser, in your buyers’ languages.

3. After 27 November 2026

   Update it

   Add the outcome of the Graubünden consultation and the next steps in the cantonal parliament.

4. Until the end of 2028

   Report each decision

   Every municipal decision is a reason to write to buyers and owners again.

A buyer who signs this winter will own their flat in January 2029. For them the reform is not news. It is the first-year bill nobody showed them. Did anyone explain it before they signed?

Ask yourself what your website answers today to “how much will it cost me each year from 2029?”. If it answers nothing, the buyer will ask another website. And who will they remember when, a few years from now, they want to sell?

If you would like me to review what a buyer finds on your website about 2029 today, start with the Strategic Diagnostic. What a flat will really cost from 2029 is for a tax adviser to calculate, not a designer.