
E-invoicing for engineering firms in Salmsach: rules, deadlines, best practice
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Salmsach.
Digitalising e-invoicing: 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 e-invoicing: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.
The Swiss legal frame for e-invoicing
Whether a business sits in Salmsach or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for e-invoicing. 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 e-invoicing run entirely on digital tools — no paper binder is required.
A well-structured SME chart of accounts
The test of a good chart of accounts is a single question: can the owner find the margins in three clicks? If not, the chart serves the tax office but not the business — even in Salmsach.
For a business in Salmsach, the Sterchi/Käfer structure also eases benchmarking: banks and fiduciaries reason on those standard classes to situate an SME's e-invoicing.

QR-bills and friction-free collections
Supplier invoices benefit from the same standard: the QR code is read on receipt, the payment is staged in e-banking with the desired due date, and the expense entry is proposed with the correct VAT. The purchase-payment-posting chain takes three moves.
Used properly, the QR reference removes most manual debtor ticking. For e-invoicing, that means reminders triggered on reliable data and continuously readable cash flow — no more waiting for month-end to know who has paid.
Salmsach: what changes, what does not
Working with a fiduciary from Salmsach no longer depends on geography: the documents of a business in Salmsach are shared online, while the canton Thurgau keeps its own deadlines for the tax return.
Federal deadlines do not move in Salmsach: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 8599 changes nothing about those rules, only the sender's address.
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 Salmsach too.
How long must records related to e-invoicing 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 Salmsach can therefore archive fully digitally.
Do you need a fiduciary for e-invoicing, or can you do it yourself?
Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Salmsach.
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 Salmsach.
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing for businesses in Salmsach: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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