
E-invoicing for construction companies in Au (SG): the practical guide
Delegate, digitalise or do it all yourself? Around e-invoicing in Au (SG), every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.
Digitalising e-invoicing: what actually works
A serious accounting document archive links every record to its entry, timestamps versions and logs access — exactly what Swiss bookkeeping regulation expects from probative electronic retention. Chronological filing by financial year becomes an automatic by-product.
For e-invoicing, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.
QR-bills and friction-free collections
Instalments and partial payments are handled cleanly with distinct references per tranche: each collection finds its share, and the remaining balance stays correct at all times.
Reference discipline remains: an invoice issued without a structured reference — or paid by a client who truncates it — becomes a manual case again. Coaching recurring clients and keeping your own outgoing payments clean keeps the automation rate at the top.
The Swiss legal frame for e-invoicing
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. E-invoicing sits squarely within this frame, including for companies based in Au (SG).
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For e-invoicing, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.

A well-structured SME chart of accounts
A chart of accounts gets documented: one description line per account (what, when, VAT) is enough for two people to post the same way. It is the quality manual of e-invoicing, valid in Au (SG) as anywhere.
For e-invoicing, a few well-chosen analytical accounts (by activity, by site) beat a forest of sub-accounts nobody ever reads.
Au (SG): what changes, what does not
Sole proprietorship, Sàrl or SA in Au (SG): the AHV contact remains the competent compensation office, and taxes follow the scales of the canton St. Gallen.
Federal deadlines do not move in Au (SG): VAT within 60 days, salary declaration in January, 10-year record retention — postal code 9434 changes nothing about those rules, only the sender's address.
Frequently asked questions
Does MyFiducia.ai work for a business based in Au (SG)?
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 Au (SG) manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Au (SG), family allowances follow the canton's rates.
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 Au (SG): federal law applies.
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 Au (SG): the CO dictates it, not the commune.
Also worth reading
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing for businesses in Au (SG): AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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