
Payroll management for engineering firms in Therwil: rules, deadlines, best practice
Payroll management for engineering firms in Therwil raises the same questions for most Swiss SME owners: which obligations apply, which deadlines are running, which documents to prepare. This page covers the federal rules in force — without unnecessary jargon.
The Swiss legal frame for payroll management
For an owner in Therwil, 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.
For payroll management, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.
Digitalising payroll management: what actually works
Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.
For an owner in Therwil, a dashboard only has value if the data is fresh: automating data entry means, first of all, buying up-to-date information about your own business.
Salaries and social contributions: the rates to know
Expense claims are payroll in the broad sense: actual reimbursements against receipts, or flat rates approved by the cantonal tax office in an expense policy. Without a clear rule, every reimbursement becomes a debate.
For payroll management, the gap between agreed gross and paid net surprises every new employer: simulate it BEFORE hiring to avoid misunderstandings with the future employee.

A Swiss SME's accounting calendar
The typical annual cycle: monthly or quarterly AHV instalments, VAT returns (quarterly under the effective method, semi-annual under the net tax rate), the final salary declaration in January, closing in the first half-year, then the tax return and the annual VAT reconciliation. Each link depends on the quality of the previous one.
Handing deadline monitoring to a tool is no luxury: automatic reminders, a status per obligation, and an “all green” view that clears the mind. What matters is not who ticks the box — but that the box exists and everyone can see it.
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.
For a business in Therwil, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Basel-Country.
Frequently asked questions
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.
What are the legal obligations for payroll management 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 Therwil: federal law applies.
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.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates payroll management for businesses in Therwil: 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.