
E-invoicing for engineering firms in Mühlau: the practical guide
E-invoicing for engineering firms in Mühlau raises the same questions for most Swiss SME owners: which obligations apply, which deadlines are running, which documents to prepare. This page covers the federal rules in force — without unnecessary jargon.
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.
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 Mühlau.
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.
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 Mühlau.
One simple principle drives e-invoicing: every franc in or out must be explainable by a document, an entry and an account. All of Swiss accounting law fits inside that traceability requirement.

Outsource e-invoicing or keep it in-house?
A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of e-invoicing lowers fees more surely than any negotiation.
A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.
Mühlau: what changes, what does not
Sole proprietorship, Sàrl or SA in Mühlau: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.
Mühlau requires no special bookkeeping: the Code of Obligations applies at postal code 5642 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
How much does e-invoicing cost in Mühlau?
It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.
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 Mühlau as anywhere.
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 Mühlau can therefore archive fully digitally.
What are the current Swiss VAT rates?
Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Mühlau.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates e-invoicing for businesses in Mühlau: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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