Collaborative desk with laptops and documents, top view

Social security contributions for startups in Würenlos: rules, deadlines, best practice

Social security contributions for startups in Würenlos 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 social security contributions

In Switzerland, the duty to keep accounts stems from art. 957 ff. of the Code of Obligations. Legal entities (Sàrl, SA) and sole proprietorships with at least CHF 500,000 in revenue keep full accounts: balance sheet, income statement and notes. Below that threshold, a simplified record of income, expenses and assets is sufficient.

The good news: the Swiss frame is stable and predictable. Structure social security contributions once — chart of accounts, document flow, calendar — and the same organisation pays off for years.

Outsource social security contributions or keep it in-house?

Outsourcing social security contributions to a fiduciary frees up time and secures compliance; keeping it in-house preserves a continuous view and costs less in fees. The best answer is often hybrid: the company captures and digitises as it goes, the fiduciary supervises, closes the books and represents the company before the authorities.

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

Two of these contributions are set by law: AHV/IV/APG at 5.3% and unemployment at 1.1%, both payable by the employer. The others — LPP, accident insurance, possibly daily sickness benefits and family allowances — depend on the insurer, the industry and the pension plan. The total surcharge usually falls between 12 and 20% of gross pay, and employee deductions between 10 and 15%: these are orders of magnitude, not statutory rates.

For social security contributions, the gap between agreed gross and paid net surprises every new employer: simulate it BEFORE hiring to avoid misunderstandings with the future employee.

Pen pointing at a bar chart on paper

Digitalising social security contributions: 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.

The winning pair for social security contributions: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.

Würenlos: what changes, what does not

Working with a fiduciary from Würenlos no longer depends on geography: the documents of a business in Würenlos are shared online, while the canton Aargau keeps its own deadlines for the tax return.

Würenlos requires no special bookkeeping: the Code of Obligations applies at postal code 5436 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

Does MyFiducia.ai work for a business based in Würenlos?

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 Würenlos manages its documents, VAT and exports exactly as anywhere in Switzerland.

How long must records related to social security contributions 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 Würenlos can therefore archive fully digitally.

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 Würenlos.

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 Würenlos.

Also worth reading

In neighbouring municipalities

Switch to accounting that keeps itself up to date

MyFiducia.ai automates social security contributions for businesses in Würenlos: 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.

    Social security contributions for startups in Würenlos