
AHV settlement for engineering firms in Lommis: rules, deadlines, best practice
AHV settlement for engineering firms in Lommis rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.
The Swiss legal frame for AHV settlement
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. AHV settlement sits squarely within this frame, including for companies based in Lommis.
One simple principle drives AHV settlement: every franc in or out must be explainable by a document, an entry and an account. All of Swiss accounting law fits inside that traceability requirement.
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.
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.
Digitalising AHV settlement: what actually works
Accounting digitalisation always follows the same path: capture documents at the source (photo or PDF upload), let automatic recognition extract supplier, amount, date and VAT, approve the proposed entries, then archive each document linked to its entry. Every step removes a re-keying — and therefore an error source.
An SME in Lommis that digitalises gains owner time first: less filing, fewer “where is that receipt?” questions, more attention to the trade — that is the real return of AHV settlement.

Outsource AHV settlement or keep it in-house?
A good test before choosing: ask the fiduciary HOW it wants to receive the documents. A precise answer (formats, frequency, platform) says more than any brochure — including in Lommis.
A business in Lommis can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — AHV settlement splits very well.
Lommis: what changes, what does not
Sole proprietorship, Sàrl or SA in Lommis: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Thurgau.
Federal deadlines do not move in Lommis: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 9506 changes nothing about those rules, only the sender's address.
Frequently asked questions
How long must records related to AHV settlement 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 Lommis can therefore archive fully digitally.
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 Lommis.
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 Lommis.
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 Lommis too.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates AHV settlement for businesses in Lommis: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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