Switzerland Lump-Sum Taxation 2026: The German DBA Trap That Extends § 2 AStG From 5 to 10 Years

What is the DBA trap in Swiss lump-sum taxation for German emigrants?

Background. Section 2 of the German Foreign Tax Act (§ 2 AStG) provides that German nationals who relocate their residence to a low-tax jurisdiction remain subject to extended German limited tax liability for a transitional period — on certain German-source income such as German rental income, German pension income, and certain participation income. This extended liability normally ends after 5 years, provided the taxpayer is comprehensively taxed under ordinary rules in the new state of residence.

A person who opts for Swiss lump-sum taxation under article 14 of the Swiss Federal Direct Tax Act (DBG) is formally Swiss-resident and Swiss-taxable, but is taxed on a flat assessment based on living costs rather than on worldwide income. The German tax authorities and the Germany-Switzerland DBA do not treat this status as treaty residence. The 5-year clock under § 2 AStG therefore does not start — it extends to 10 years.

The extension is not an isolated rule but a direct consequence of treaty mechanics: where the DBA cannot allocate primary taxing rights to Switzerland (because the taxpayer is not treaty-resident), Germany retains its taxing right and § 2 AStG activates the maximum 10-year window.

External reading: EY Germany — § 6 AStG and ETFs from 2025 (German tax exit-tax expansion)

Related Mirabello guide: Moving to Switzerland 2026: Unlimited Deferral of § 6 AStG Exit Taxation (German-language guide) →

Why does § 2 AStG extend from 5 to 10 years specifically under lump-sum taxation?

§ 2 AStG explicitly distinguishes two configurations:

• 5 years of extended limited tax liability — where the destination state imposes ordinary tax "comparable to German taxation" on worldwide income
• 10 years of extended limited tax liability — where it does not (e.g. low-tax states or special regimes that do not capture worldwide income)

Swiss lump-sum taxation explicitly does not tax worldwide income. It taxes a flat assessment based on living costs (federal floor: seven times annual housing cost, minimum CHF 435,000 assessment basis in 2026). The German tax authorities, as a settled matter of practice, classify this regime as "not comparable to German taxation" — and therefore activate the 10-year window under § 2 AStG.

By contrast, a German emigrant who is taxed in Switzerland on the ordinary cantonal scale (declaring worldwide income, taxed on the cantonal tariff) does meet the "comparability" test. The 5-year window applies, and after five years the German extended limited tax liability ends definitively.

The 5-year difference matters in practice. It determines whether a German emigrant with German rental income, German participation income below the 1% threshold, or German pension entitlements remains within German tax reach for 5 years or for 10 years.

How does the 5-years-ordinary-then-lump-sum mitigation work in practice?

The strategy is conceptually simple but operationally demanding. Mirabello Consultancy structures it in four phases:

• Phase 1 — Emigration + ordinary Swiss taxation (years 1-5): On emigrating from Germany to Switzerland, the taxpayer elects ordinary Swiss taxation in the new canton of residence. Worldwide income is declared (as for any ordinary Swiss tax resident). The Germany-Switzerland DBA recognises this as "comparable" to German taxation; § 2 AStG runs for 5 years.
• Phase 2 — Exit-tax deferral (in parallel): Section 6 AStG (German exit tax on shareholdings, ETF and fund holdings) is deferred without limit and without interest on emigration to Switzerland under BMF administrative practice and the DBA. The deferral applies regardless of whether the taxpayer chooses ordinary or lump-sum taxation. Full mechanics in the Mirabello § 6 AStG / ETF guide (German-language) →
• Phase 3 — End of the § 2 AStG window (after year 5): At the end of year 5, the German extended limited tax liability ends. From this point on, Germany has no extended right to tax German-source income beyond ordinary limited-tax-liability rules.
• Phase 4 — Optional switch to lump-sum taxation (year 6 onwards): After § 2 AStG has expired, the taxpayer can apply for a switch to lump-sum taxation in the canton of residence — provided that canton offers the regime (see table below). From this point the disclosure of worldwide income to the Swiss authorities ceases and the lump-sum assessment based on living costs applies.

Which Swiss cantons still offer lump-sum taxation in 2026?

Lump-sum taxation is permitted at the federal level across Switzerland, but each canton offers or refuses it independently. Status 2026:

Source for the federal floor: Swiss Federal Tax Administration (ESTV) — Aufwandbesteuerung.

For German HNWIs implementing the mitigation strategy, the cantons that come up most often in Mirabello's practice are:

• Zug: Lowest income tax in Switzerland, international HNWI environment, lump-sum taxation available — ideal for Phase 4 (the optional switch after year 5).
• Schwyz: Lowest overall tax burden in Switzerland, lump-sum taxation on attractive terms — strategic primary canton for retired or non-active HNWIs.
• Valais and Ticino: Lump-sum taxation with lower minimum assessment bases, high quality of life, Italian/French-speaking environment.
• Zurich: Lump-sum taxation abolished — but for Phase 1 (ordinary taxation in the first 5 years) Zurich is highly defensible: best financial, schooling and business environment in Switzerland. A move to a lump-sum-eligible canton is required in Phase 4.

Companion guide: Mirabello main guide on emigrating to Switzerland 2026: cantonal selection, § 6 AStG deferral, CBI strategy (German-language) →

Is Swiss lump-sum tax creditable against German tax?

The German credit rules under § 34c EStG require that the foreign state has imposed a tax comparable to the German tax on the same items of income. Swiss lump-sum taxation systematically fails this test because:

• The lump-sum tax is not levied on actual income but on a flat assessment (living costs × factor)
• The lump-sum tax cannot be allocated to specific income categories (e.g. German rental income, German participation income)
• There is no identity of taxable base between the German § 2 AStG charge and the Swiss lump-sum charge

Practical consequence: without mitigation planning, a lump-sum-taxed German emigrant may carry double taxation for the first 10 years — the German § 2 AStG tax on German-source income alongside the Swiss lump-sum tax on Swiss living costs. For a German rental portfolio earning EUR 200,000 net per year, that means 10 years of full German income tax on those rentals while Swiss lump-sum tax of typically CHF 100,000-150,000 per year is paid in parallel.

The 5-years-ordinary-then-lump-sum strategy resolves this structurally by shortening the § 2 AStG window to 5 years and deferring the lump-sum switch until after the German tax shadow has expired.

How does a second citizenship (CBI) fit into the Switzerland lump-sum strategy?

Since Germany's June 2024 citizenship reform (the Act to Modernise Nationality Law), German citizens may acquire a second citizenship without renouncing the German one. The reform has fundamentally changed the strategic logic for German HNWIs: a second citizenship can now be held in parallel — without a release declaration, without a retention permit.

For German HNWIs taxed on a Swiss lump-sum basis, the CBI programmes that come up most often in Mirabello's advisory practice are:

• Grenada — USD 235,000: 144+ visa-free destinations including the UK, Schengen, Singapore, China. The only Caribbean programme with US E-2 Investor Visa access. Strategic passport for US market access without a green card. Grenada Citizenship by Investment 2026 →
• St. Kitts & Nevis — USD 250,000: 157 visa-free destinations. The US FinCEN advisory was rescinded in February 2026 — banking access materially improved. Fast processing, established programme track record since 1984.
• Antigua & Barbuda — USD 230,000: Family-friendly programme — up to four family members included with no surcharge. 165+ visa-free destinations. 5-day residence requirement in 5 years.
• Dominica — USD 200,000: Lowest-cost Caribbean CBI after São Tomé and Nauru. 140+ visa-free destinations.
• Vanuatu — USD 130,000: Fastest CBI in the world (30-60 days). No residence requirement. Note: EU Schengen visa-free access is currently suspended (since December 2024).

Full programme overview: Best Citizenship by Investment Programmes 2026 → | Residence rather than citizenship? Best Golden Visa Programmes 2026 →

What questions do German HNWIs ask about the lump-sum DBA trap?

Does the DBA trap also apply if I live in one of the abolished cantons (Zurich, Basel-Stadt, Basel-Land, Schaffhausen, Appenzell Ausserrhoden)?
No. In a canton that has abolished lump-sum taxation, every taxpayer is taxed on the ordinary cantonal scale. The Germany-Switzerland DBA recognises this ordinary taxation as "comparable" to German taxation, and the § 2 AStG window runs 5 years on schedule. The DBA trap arises only on active election of lump-sum taxation.

Can I really switch to lump-sum taxation after 5 years without difficulty?
The switch is possible but requires a fresh application to the Swiss canton of residence. The Swiss conditions for lump-sum taxation must be met (foreign nationality, no gainful activity in Switzerland, first-time residence or at least 10 years of absence). Anyone moving to a different canton must file the application again. Mirabello Consultancy coordinates the switch with Swiss fiduciary partners.

What happens to my ETF portfolio in Phase 1 (ordinary taxation)?
The Swiss tax system imposes no capital gains tax on the disposal of private securities and ETFs in private wealth — irrespective of whether the person is taxed on the ordinary scale or on a lump-sum basis. Selling ETFs in Phase 1 attracts zero Swiss CGT. The German § 6 AStG exit tax assessed on the deemed gain at the date of emigration remains deferred without limit (BMF Switzerland special rule). Full mechanics: Mirabello § 6 AStG / ETF guide (German-language).

How much is the Swiss lump-sum tax in practice?
The federal minimum assessment basis 2026 is CHF 435,000 (seven times annual housing cost as a lower limit). On that basis the federal direct tax of 11.5% gives roughly CHF 50,000, plus the cantonal and communal tax (which varies considerably — substantially lower in Schwyz and Zug than in Geneva or Vaud). Effective total tax in a preferred canton typically lands between CHF 120,000 and CHF 200,000 per year, depending on canton and assessment basis.

How do I begin the lump-sum mitigation strategy with Mirabello Consultancy?
The first step is a complimentary consultation with our experts in Zurich. We analyse your relocation goals, your German-source income (relevant for § 2 AStG) and your wealth structure, and produce an individual roadmap. Mirabello Consultancy is headquartered in Zurich and coordinates the entire emigration structure: § 6 AStG planning, cantonal tax setup, optional lump-sum switch after year 5, and any CBI application. Book your complimentary consultation →