
VAT return with AI in Arbon: 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 VAT return in Arbon: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for VAT return
Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Arbon.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For VAT return, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.
Digitalising VAT return: what actually works
Access for the fiduciary, the auditor and employees is set by roles: view, enter, approve, close. Well-set rights protect the data and speed up collaboration.
The selection criterion for a tool is not the length of its feature list but the robustness of the daily flow: reliable bank imports, VAT computed correctly (8.1 / 2.6 / 3.8%), a complete audit trail from document to entry, and a clean export for the auditor or fiduciary. Everything else is secondary.
Outsource VAT return or keep it in-house?
A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of VAT return lowers fees more surely than any negotiation.
Changing fiduciary is not a drama: the accounting data belongs to the company, and a clean export (entries, chart of accounts, linked documents) allows a transition at year-end. A provider who locks in a client's data says a lot about how it works.

Swiss VAT: rates, threshold and filings
A VAT return is prepared, not endured: clean VAT accounts, one code per rate and a monthly variance check make the deadline trivial — for registered businesses in Arbon too.
A business in Arbon that crosses the threshold mid-year must register without delay: retroactive registration with interest always costs more than signing up on time.
Arbon: what changes, what does not
Arbon (postal code 9320, canton Thurgau) applies the same federal rules as the rest of the country: what changes in Arbon are the cantonal counterparts — tax administration, compensation office, commercial register.
For a business in Arbon, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Thurgau.
Frequently asked questions
Do you need a fiduciary for VAT return, or can you do it yourself?
Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Arbon.
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 Arbon too.
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 Arbon as anywhere.
How long must records related to VAT return be kept?
Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders. A business in Arbon can therefore archive fully digitally.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates VAT return for businesses in Arbon: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
The application is operated in French.