
Everything that matters about social security contributions for engineering firms in Boningen
Whether you run a Sàrl, an SA or a sole proprietorship in Boningen, social security contributions 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 social security contributions
Whether a business sits in Boningen or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for social security contributions. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
The law also settles the form: accounts may be kept in a national language or in English, on paper or electronically (art. 957a para. 5 CO). That pragmatism lets social security contributions run entirely on digital tools — no paper binder is required.
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 social security contributions, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.
Outsource social security contributions 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 social security contributions lowers fees more surely than any negotiation.
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
Absences are managed upstream: illness, accident, military service or maternity trigger allowances (APG, insurance) that replace part of the salary. Clean absence records are the basis of correct settlements, in Boningen as elsewhere.
Withholding tax applies to foreign employees without a C permit: the employer deducts tax at the cantonal rate and remits it. The annual salary certificate remains mandatory for all staff — it is the linchpin connecting payroll accounting, tax returns and AHV audits.
Boningen: what changes, what does not
Working with a fiduciary from Boningen no longer depends on geography: the documents of a business in Boningen are shared online, while the canton Solothurn keeps its own deadlines for the tax return.
For a business in Boningen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Solothurn.
Frequently asked questions
Does MyFiducia.ai work for a business based in Boningen?
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 Boningen manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Boningen.
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 Boningen too.
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 Boningen: the CO dictates it, not the commune.
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MyFiducia.ai automates social security contributions for businesses in Boningen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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