
SME tax return common mistakes in Wettingen: rules, deadlines, best practice
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on SME tax return in Wettingen: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for SME tax return
For an owner in Wettingen, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.
The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.
Swiss VAT: rates, threshold and filings
Exports, services abroad, acquisition tax: as soon as anything international enters the picture, VAT gets demanding (place of supply, acquisition tax on services). Better to set the rules once with a professional than to correct three financial years.
The net tax rate method simplifies life for small structures: one flat industry rate applied to turnover, with semi-annual filing. In exchange, input VAT is not deducted separately. The effective-versus-flat-rate choice should be reviewed periodically against the cost structure.
Year-end closing: how the mechanics work
The order of operations matters: reconciliations first (bank, cash, receivables, payables), then the closing entries, finally the VAT and AHV consistency checks. Reversing the order means starting over.
For SME tax return, the golden rule is to discover nothing in January: every uncertainty (doubtful receivable, dispute, unsellable stock) must be identified before the closing date, not after.

Outsource SME tax return or keep it in-house?
The Swiss fiduciary market is dense and governed by professional practice: industry standards, business secrecy, civil liability. Compare offers on three concrete criteria — exact scope (data entry? closing? payroll? VAT?), a named contact person, and the tools used. It prevents year-end misunderstandings.
In Wettingen, as everywhere, the right collaboration rhythm follows the activity: monthly for payroll and data entry, quarterly for VAT, yearly for the closing and tax advice.
Wettingen: what changes, what does not
Working with a fiduciary from Wettingen no longer depends on geography: the documents of a business in Wettingen are shared online, while the canton Aargau keeps its own deadlines for the tax return.
Federal deadlines do not move in Wettingen: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5430 changes nothing about those rules, only the sender's address.
Frequently asked questions
What are the legal obligations for SME tax return in Switzerland?
The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Wettingen: federal law applies.
When is entry in the commercial register mandatory?
A Sàrl and an SA only come into existence with their registration. A sole proprietorship must register from CHF 100,000 of annual revenue; below that, registration stays voluntary but adds credibility and protects the business name. Registration goes through the canton's commercial register office — for Wettingen too.
What is simplified bookkeeping and who can use it?
Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Wettingen.
Effective VAT method or net tax rate: how to choose?
The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Wettingen as anywhere.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates SME tax return for businesses in Wettingen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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