E-invoicing for engineering firms in Aarau: the practical guide
E-invoicing for engineering firms in Aarau 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.
Digitalising e-invoicing: what actually works
Access for the fiduciary, the auditor and employees is set by roles: view, enter, approve, close. Well-set rights protect the data and speed up collaboration.
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.
Outsource e-invoicing or keep it in-house?
Responsibility stays with the client: the fiduciary executes with care, but the signed accounts bind the company. Understanding what you sign is not optional.
For e-invoicing, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.
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.
For e-invoicing, the share of collections matched automatically is a metric worth watching: when it drops, it is almost always a matter of misused references.
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 a business in Aarau, the Sterchi/Käfer structure also eases benchmarking: banks and fiduciaries reason on those standard classes to situate an SME's e-invoicing.
Aarau: what changes, what does not
Sole proprietorship, Sàrl or SA in Aarau: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
For a business in Aarau, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
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 Aarau.
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 Aarau: federal law applies.
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 Aarau can therefore archive fully digitally.
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 Aarau.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing for businesses in Aarau: 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.