
Everything that matters about SME tax return required documents in Therwil
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 Therwil: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for SME tax return
A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Therwil as anywhere.
The good news: the Swiss frame is stable and predictable. Structure SME tax return once — chart of accounts, document flow, calendar — and the same organisation pays off for years.
Outsource SME tax return or keep it in-house?
Splitting roles clearly avoids duplication: the company captures documents and approves payments; the fiduciary checks postings, closes the year and defends the file before the authorities. Each side does what it does best — and nobody keys the same invoice twice.
For SME tax return, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.
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.
Delays rarely come alone: neglected bookkeeping postpones the closing, hence the tax return, hence the recalculated instalments — and the business flies blind for months. Keeping the books current as you go is the only sustainable way to hold every cascading deadline.

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 an SME in Therwil, the closing is also decision time: distributions, provisions, investments to anticipate. A file ready in February leaves time to decide; one ready in June just endures.
Therwil: what changes, what does not
Working with a fiduciary from Therwil no longer depends on geography: the documents of a business in Therwil are shared online, while the canton Basel-Country keeps its own deadlines for the tax return.
Therwil requires no special bookkeeping: the Code of Obligations applies at postal code 4106 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
How long must records related to SME tax 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 Therwil can therefore archive fully digitally.
What is the difference between a limited and an ordinary audit?
The ordinary audit applies to companies exceeding, for two consecutive years, two of three thresholds: CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions. Others fall under the limited audit, and those with no more than ten full-time positions on annual average can opt out with all shareholders' consent. These federal thresholds do not depend on the registered seat — in Therwil as anywhere.
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 Therwil.
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 Therwil too.
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MyFiducia.ai automates SME tax return for businesses in Therwil: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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