
Everything that matters about social security contributions for engineering firms in Bogis-Bossey
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on social security contributions in Bogis-Bossey: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for social security contributions
Swiss accounting law has been unified in the Code of Obligations since 2013: the same bookkeeping rules (art. 957a CO) and retention rules (art. 958f CO — 10 years for books, vouchers and reports) apply regardless of legal form. Social security contributions sits squarely within this frame, including for companies based in Bogis-Bossey.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For social security contributions, 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 social security contributions 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 social security contributions, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.
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.
An often underestimated point: self-employed status is granted by the compensation office — or not. Whoever invoices essentially one main client risks requalification as an employee, with contribution arrears charged to the principal. Clarifying AHV status before starting avoids that trap.

A Swiss SME's accounting calendar
The professionals' trick: handle every deadline at D-30, not D-1. A VAT return prepared a month early leaves time to chase a missing document without penalty.
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.
Bogis-Bossey: what changes, what does not
Working with a fiduciary from Bogis-Bossey no longer depends on geography: the documents of a business in Bogis-Bossey are shared online, while the canton Vaud keeps its own deadlines for the tax return.
For a business in Bogis-Bossey, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Vaud.
Frequently asked questions
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 Bogis-Bossey as anywhere.
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 Bogis-Bossey too.
Does MyFiducia.ai work for a business based in Bogis-Bossey?
Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Bogis-Bossey manages its documents, VAT and exports exactly as anywhere in Switzerland.
Which documents should be prepared for the year-end closing?
Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in Bogis-Bossey: the CO dictates it, not the commune.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates social security contributions for businesses in Bogis-Bossey: 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.