A Geneva resident almost never encounters the Lex Weber at home — they encounter it the day they buy a chalet in Valais, an apartment in Verbier or a pied-à-terre in Graubünden. Since the vote of 11 March 2012 and the entry into force of the Secondary Residences Act (LRS) in 2016, such purchases have followed precise rules — tightened in places, relaxed by the October 2024 revision. Here is the buyer’s guide.
The 20% rule — and where it applies
The principle: in any municipality where secondary residences exceed 20% of the housing stock, no new secondary residence may be authorised. New dwellings there are built subject to a use restriction — principal residence or qualified tourist accommodation — and this restriction is entered in the land register: it follows the dwelling, not the owner. The Confederation publishes an annual inventory of the municipalities concerned — most Alpine resorts appear on it. The first check, then, is the municipality’s rate, followed by the land register extract for the property in question, where any use restriction appears in black and white.
The key to the market: old-law dwellings
Here is what most buyers do not know — and what explains why the resort market remains very much alive: dwellings created before 11 March 2012 — known as “old-law” dwellings — can be freely used, sold and bought as secondary residences, even in a saturated municipality. The Lex Weber freezes new construction; it does not touch the existing stock. In practice: a 1970s chalet in Verbier can be bought with no use restriction — and this is precisely why these old-law properties carry a premium in municipalities that have exceeded the quota: they are the only door that will remain open.
The October 2024 revision: old-law dwellings gain value
Since 1 October 2024, the revised law has clearly relaxed the treatment of old-law dwellings in municipalities exceeding 20%: their habitable floor area may be enlarged by up to 30%, including in cases of demolition and reconstruction — and conversion or reconstruction may now create additional dwellings. For an owner or a buyer, the calculation changes: an ageing old-law chalet is no longer just a property to renovate, it is a potential — to modernise, enlarge, or even densify. The value of this potential must be assessed case by case, but the direction is clear: the revision has made the old-law stock even more valuable.
A municipality’s rate is not fixed
The 20% threshold is not a label attached once and for all: it is recalculated every year, and a municipality can cross it in either direction. The mechanism is set. Municipalities are required to compile an inventory of dwellings, entering all dwellings in their territory into the Federal Register of Buildings and Dwellings; the Federal Statistical Office checks the quality of this data by cross-referencing it with residents’ registration records, which makes it possible to identify principal residences. The Federal Office for Spatial Development then calculates the proportion and publishes the inventory at the end of March, based on the situation as at the preceding 31 December.
When a municipality crosses the threshold, a verification procedure opens with the canton before the change takes effect. For a buyer, the consequence is concrete: a municipality may exit the restrictive regime and reopen the construction of secondary residences — which weighs on the premium of old-law properties — or enter it, freezing projects that the seller presented to you as settled. A permit that has been granted remains a permit granted; a project merely envisaged does not. Check the current year’s publication, not a dated article.
Buying in a resort from Geneva: the three questions
1. The status of the dwelling — old law (freedom) or new law (restricted use recorded in the land register): this is the question that governs everything, and it must be verified, not assumed. 2. Financing — a secondary residence is financed more strictly than a principal residence: banks require a higher equity contribution, and above all no withdrawal of second-pillar pension funds, which the law reserves for the principal residence. Our financing guide and the mortgage simulator set out the basics of the calculation. 3. The buyer’s status — for a person domiciled in Switzerland, the Lex Weber is the only filter; for a buyer from abroad, the Lex Koller also applies, with its cantonal quotas for holiday homes. The two laws apply together — one looks at the dwelling, the other at the buyer.
Selling or transferring a secondary residence
On the seller’s side, the mechanism works in mirror image: an old-law property sells without restriction and targets the widest possible market; a new-law property sells with its designated use — to a buyer who will occupy it as a principal residence or operate it as tourist accommodation. On inheritance, the regime follows the dwelling: inheriting an old-law chalet changes nothing — it remains freely usable. And for anyone selling their secondary residence in order to buy elsewhere, the sell-and-buy-back mechanism applies as for any property — capital gains tax is settled at the location of the property.
And in Geneva itself?
The canton is not a land of secondary residences — the question of the quota barely arises there, and it is by buying elsewhere that a Geneva resident encounters this law. It is nonetheless one of the five public-law regimes that thorough due diligence systematically checks before any purchase, wherever the property is located. Technical terms are explained in the glossary — and if your Alpine project accompanies a reorganisation of your Geneva assets, let’s discuss it: it is often part of the same process.