Selling property in the Canton of Aargau
Selling in Aargau: your purchase price does not always count for tax.
After more than ten full years, a flat share replaces a house's purchase price and improvements. In the worked example, this cuts the tax by almost half.
As of September 2026 · Tax Act of the Canton of Aargau (SAR 651.100), version of 1 January 2025 · property gains tax guidance (Merkblatt Grundstückgewinnsteuer), amended 1 July 2023.
What most people overlook: after decades, Aargau does not always tax the whole rise in value. A worked example over 36 years shows CHF 19,000 less tax.
Tax when you sell
Selling a house in the Canton of Aargau: how much tax do I pay after many years?
After 25 full years, Aargau's property gains tax is 5 %. It taxes the gain: sale price minus investment costs (Anlagekosten) – purchase price and improvements like an extension. After more than ten full years, a flat share of a house's sale price replaces them. It is 80 %, then 65 % from 25 full years.
An example: bought in 1990 for CHF 400,000, sold in 2026 for CHF 1,200,000. With CHF 780,000 as flat-share costs, the taxed gain is CHF 420,000: CHF 21,000 in tax, against CHF 40,000 on the purchase price alone. Worked out under §§ 105 and 109 Aargau Tax Act, as of 1 January 2025. The cantonal tax office's guidance (section 11.1.1) does likewise.
What this means for you: after 25 full years, waiting saves no more tax. In the example, receipts only pay off once purchase price and documented costs exceed CHF 780,000. Then everything fully documented counts, not the flat share. Try both in the Aargau tax calculator.
Whether the flat share or your receipts mean less tax also depends on the sale price: the flat share grows with it, receipts do not. No calculator knows that price; the valuation gives it as a range. The net calculation also shows what you keep after tax, mortgage and selling costs. You receive it in writing, so parents and children can check the same figure before anyone signs.
Process and costs
Selling a house in Aargau: what costs are due at the notary?
Around the notary appointment, a house sale in Aargau mainly costs the 0.4 % land register charge and notarisation (Beurkundung). There is no transfer tax, but changing hands is not free. The charge is due on entry in the land register (Grundbuch), the ownership record. Who pays is open; both sides are jointly liable (§§ 5 and 8 Land Register Charges Act, as of 1 January 2020).
At CHF 1,200,000, the charge is CHF 4,800. Notarisation costs CHF 3,600 under the notarial tariff, plus value added tax and expenses. Only an Aargau notary (Urkundsperson) may notarise the sale. A statutory 3 % lien on the price secures the property gains tax. It is not a tax and lapses if other security is given.
What this means for you: if you replace a home you live in, the municipality usually bills the tax first without deferral. So plan for that bill before signing. You apply for the deferral yourself, without an agent. See how a sale with Immosmile works.
What is different here
What you should know about selling in the Canton of Aargau.
Your years of ownership count twice
In Aargau, your years of ownership set both the tax rate and the flat share, each by its own table. The rate falls in 26 steps: by 2 percentage points a year to 20 % in year eleven, then by one point to 6 %. From 25 full years, the rate is 5 % and the flat share 65 % of the sale price. There is no tax-free threshold and no tax multiplier (Steuerfuss); canton and municipality each receive half the revenue.
Only what goes into the new home is deferred
If you sell a house or flat you live in permanently and exclusively, you can apply for a deferral (§ 98 Tax Act). The new home must be in Switzerland, bought or built within two years before or three years after the sale. If it costs no more than your investment costs, nothing is deferred. In a building with several flats, only the part you live in counts.
3 % as a lien, not as a tax
Since 2020, a statutory lien of 3 % of the price has secured property gains tax, without a land register entry (§ 234a Tax Act). It secures only the tax actually owed. It lapses if other security is provided, for example by paying 3 % to the office that collects the tax. To arrange this, the notary or the parties contact the tax office (Steueramt) where the property lies.
Districts and municipalities
196 municipalities in eleven districts – from Rheinfelden to Muri.
Twelve municipalities from all eleven districts, following the official district division. We are happy to talk about your property in person.
Getting there
From the office at Bahnhofplatz Zurich
By train from Zurich HB, fastest connection on a weekday from 9 am (SBB timetable 2026, checked on 30 September 2026).
- Zurich HB → Baden 15 min · direct
- Zurich HB → Aarau 24 min · direct
- Zurich HB → Brugg 24 min · direct
- Zurich HB → Wohlen 32 min · 1 change
Questions from the Canton of Aargau
What owners here want to know.
How high is property gains tax in the Canton of Aargau?
Between 40 and 5 % of the gain, depending on how long you have owned the property. It is 40 % in year one, 20 % in year eleven and 5 % from 25 full years (§ 109 Aargau Tax Act). There is no tax multiplier (Steuerfuss) and no surcharge. The municipality where the property lies assesses the tax.
Is a small gain taxed in the Canton of Aargau?
Yes. The Canton of Aargau has no tax-free threshold, so every franc of gain is taxable (§§ 101 and 109 Aargau Tax Act). In the first year of ownership, 40 % applies: a CHF 12,000 gain means CHF 4,800 in property gains tax.
Can I defer the tax in the Canton of Aargau if I buy a new home?
Yes, on request, as a replacement purchase (Ersatzbeschaffung): a tax deferral when the proceeds go into a new home of your own. You must live in both the old and the new home permanently and exclusively. The new home is bought or built in Switzerland, within two years before or three years after the sale. Only the part of the proceeds you reinvest is deferred (§ 98 Aargau Tax Act).
Is there a transfer tax in the Canton of Aargau?
No, not a conventional one. But on every sale the canton levies a land register charge (Grundbuchabgabe) of 0.4 % of the purchase price, at least CHF 100. Buyer and seller are jointly liable for it; the law does not say who bears it (§§ 5 and 8 Land Register Charges Act).
Who notarises the purchase contract in the Canton of Aargau?
A notary authorised in Aargau (Urkundsperson), whose authority comes from the notarial commission (Notariatskommission). Purchase contracts for Aargau property must be notarised in the canton. Deeds from other cantons do not count for this (§§ 5 and 6 Notarisation and Certification Act). The fee is set by the notarial tariff and is the same for all parties.
Inherited a house in the Canton of Aargau: do my parents' purchase price and years of ownership count?
Yes, as a rule your parents' purchase price and the years since their purchase count. Inheritance, gifts and advances on inheritance (Erbvorbezug) only defer property gains tax (§ 97 Aargau Tax Act). What counts is the last taxed change of ownership, usually your parents' purchase (§§ 103 and 110). If that was more than ten full years ago, the flat share applies to a house where it exceeds documented costs (§ 105).
Can an estate agent based in Zurich handle a sale in the Canton of Aargau?
Yes, and we apply Aargau law, even though the office of Immosmile GmbH is at Bahnhofplatz 1 in Zurich. We work with Aargau's rate by years owned, its flat share for investment costs and its land register charge, not Zurich's scale. Your only contact, from the first conversation to the notarised deed, is managing director Dominik Devaja. The valuation is free and without obligation, even if we recommend keeping the house.
What does buying cost in the Canton of Aargau?
No classic transfer tax, but a land registry levy (Grundbuchabgabe) of 0.4 %, at least CHF 100 (§ 8 GBAG). Land registry and notarisation fees come on top. For a purchase price of CHF 1 million, the buyer pays CHF 3,730 to 7,459, depending on the purchase contract and excluding mortgage notes (as of 30 September 2026).
All eight cantons and a calculator: purchase costs by canton.
Sources
- Tax Act of the Canton of Aargau (SAR 651.100) (German)
- Property gains tax guidance – Cantonal Tax Office Aargau (German)
- Land Register Charges Act (SAR 725.100) (German)
- Notarisation and Certification Act (SAR 295.200) (German)
- Decree on the notarial tariff (SAR 295.250) (German)
- Canton of Aargau in figures – Statistik Aargau (German)
General information, not tax advice. You receive the exact calculation for your property in the free valuation.
Your contact for the Canton of Aargau
Want to know what you keep in Aargau after many years of ownership? Call me.
From Bahnhofplatz in Zurich, I can be in Baden in 15 minutes and in Aarau in 24. You get an honest assessment – even if it says «wait».
