
Everything that matters about e-invoicing for engineering firms in Stüsslingen
Whether you run a Sàrl, an SA or a sole proprietorship in Stüsslingen, e-invoicing eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Digitalising e-invoicing: 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.
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.
A well-structured SME chart of accounts
Shareholder current accounts demand strict hygiene: every private withdrawal documented, interest at the rates accepted by the tax administration, and a clean-up at closing.
For e-invoicing, the right granularity is decisive: enough accounts to steer the business (margins by activity, expenses by nature), few enough that every entry finds its place without hesitation. The VAT accounts (input VAT, VAT due) deserve special care — they are the basis of the annual reconciliation.
QR-bills and friction-free collections
Technically, two routes coexist: the classic IBAN with an optional reference, or the QR-IBAN which requires a structured 27-position QR reference. Only the second route makes matching truly automatic — every payment carries the exact identifier of its invoice.
The winning trio remains: QR-bills for collections, e-banking connected to the accounts for statement imports (camt.053), and automatic matching rules. Exceptions — partial payments, duplicates, missing references — are then handled in minutes, not hours.

The Swiss legal frame for e-invoicing
Responsibility for the books is personal: in an SA, organising the accounting is one of the board's non-transferable duties (art. 716a CO); in a Sàrl, the managing directors carry the same duty. Outsourcing the execution never transfers that underlying responsibility, including for a company based in Stüsslingen.
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.
Stüsslingen: what changes, what does not
Working with a fiduciary from Stüsslingen no longer depends on geography: the documents of a business in Stüsslingen are shared online, while the canton Solothurn keeps its own deadlines for the tax return.
Stüsslingen requires no special bookkeeping: the Code of Obligations applies at postal code 4655 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
Effective VAT method or net tax rate: how to choose?
The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Stüsslingen 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 Stüsslingen too.
What are the legal obligations for e-invoicing in Switzerland?
The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Stüsslingen: federal law applies.
Which social contributions does a Swiss employer pay?
AHV/IV/APG: 5.3% employer share (the same is withheld from the employee); unemployment insurance: 1.1% each up to CHF 148,200 a year; occupational pension (LPP) by age and plan (employer at least 50%); occupational accident insurance paid by the employer; family allowances by canton. For an employer in Stüsslingen, family allowances follow the canton's rates.
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