
E-invoicing for plumbers in Killwangen: rules, deadlines, best practice
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on e-invoicing in Killwangen: what the law requires, what can be automated, and when to delegate.
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 an owner in Killwangen, a dashboard only has value if the data is fresh: automating data entry means, first of all, buying up-to-date information about your own business.
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 Killwangen as anywhere.
For e-invoicing, a few well-chosen analytical accounts (by activity, by site) beat a forest of sub-accounts nobody ever reads.
QR-bills and friction-free collections
The QR-bill is generated from the accounts, not the other way round: the document is born with its reference, amount and due date already linked to the receivable entry — a clear win for SMEs in Killwangen.
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 Killwangen.
Also worth knowing: accounts may be drawn up in the currency most relevant to the business; if that is not the franc, values must additionally be stated in CHF (art. 958d para. 3 CO). Internationally active companies gain books that match their economic reality.
Killwangen: what changes, what does not
Sole proprietorship, Sàrl or SA in Killwangen: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
Killwangen requires no special bookkeeping: the Code of Obligations applies at postal code 8956 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Killwangen.
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 Killwangen: federal law applies.
Can e-invoicing be automated with AI?
Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches e-invoicing.
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 Killwangen, family allowances follow the canton's rates.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing for businesses in Killwangen: 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.