Selling property in Gossau: what buyers may build

First of all, it does not affect every plot. It is only charged on planning benefits from upzoning or rezoning, that is when more or different building is now allowed.⁶ Gossau charges 40 per cent of the gain in value minus CHF 100,000. Cantonal law allows no more.⁸

The exempt area is also at the strict end. Plots under 1,200 square metres are generally exempt, the lowest threshold the law permits.⁸ Larger plots in Gossau are therefore more likely to be covered than in municipalities with a threshold of 2,000 square metres.

The levy only falls due on development, not on a sale.⁹ The obligation passes to the buyer and belongs in the sale contract.⁸ What this means for you: anyone buying to build anew will factor the levy into the offer. So clarify before you advertise whether your plot is affected.

The value capture levy is now set out in articles 34a and 34b of the building regulations.⁶ Gossau has partially revised its building and zoning regulations; the new version has applied since 1 September 2026. The levy rules were carried over word for word. They have been in force since January 2023.⁷

Whether your plot was upzoned or rezoned shows in a comparison of the old and new zoning plans. The building office can confirm it with binding effect. Once a levy is set, it is noted in the land register.⁸ At the latest then, every buyer who reads the extract sees it too.

What this means for you: with a small plot and no zoning change, the matter is quickly settled. With a large plot that has reserves, the question belongs in the valuation. The cantonal model puts residential building land in Gossau at CHF 1,491 per square metre in 2025, 71 per cent more than in 2015.¹¹

In the median example, CHF 137,424. Take a house bought at the 2007 median of CHF 660,000. Sold at the 2025 median of CHF 1,300,000, it gains CHF 640,000.² The tax takes 21.5 per cent of that gain and 10.6 per cent of the sale price.¹

For flats the picture is hardly different. The flat median was CHF 480,000 in 2007 and CHF 1,125,000 in 2025.² At CHF 645,000, the gain is even slightly larger than for the house, and so is the tax at CHF 138,544. The canton sets the tariff; Gossau only levies the tax.¹

After 20 full years the tax is halved, to CHF 122,700 in the house example.¹ Documented value-adding investments reduce the gain; ordinary maintenance does not. What this means for you: house or flat, in Gossau your own purchase price counts. Bring your purchase contract to the first meeting.