
Accounting checklist in Sommeri: rules, deadlines, best practice
Whether you run a Sàrl, an SA or a sole proprietorship in Sommeri, accounting eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
The Swiss legal frame for accounting
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Sommeri with a clean audit trail sails through these exercises.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For accounting, 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.
Outsource accounting or keep it in-house?
Outsourcing does not exempt you from understanding: an owner who can read the balance sheet and the income statement challenges the fiduciary better — and pays for advice, not re-keying.
A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.
A Swiss SME's accounting calendar
Every deadline has an owner: an obligation “of everyone” is kept by no one. Naming one person per deadline family (VAT, payroll, taxes) closes the gaps.
For accounting, deadline discipline is worth real money: default interest on late VAT, AHV adjustments, tax fines. A shared deadline calendar — fed by up-to-date figures — remains the simplest safeguard.

A well-structured SME chart of accounts
The same chart serves three readings: accounting (accuracy), tax (accepted adjustments) and management (margins by activity). Modern software produces all three views without double entry.
For a business in Sommeri, the Sterchi/Käfer structure also eases benchmarking: banks and fiduciaries reason on those standard classes to situate an SME's accounting.
Sommeri: what changes, what does not
Sommeri (postal code 8580, canton Thurgau) applies the same federal rules as the rest of the country: what changes in Sommeri are the cantonal counterparts — tax administration, compensation office, commercial register.
For a business in Sommeri, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Thurgau.
Frequently asked questions
How much does accounting cost in Sommeri?
It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.
Do you need a fiduciary for accounting, 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 Sommeri.
What are the current Swiss VAT rates?
Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Sommeri.
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 Sommeri.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting for businesses in Sommeri: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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