
SME tax return step by step in Erlen: the practical guide
Whether you run a Sàrl, an SA or a sole proprietorship in Erlen, SME tax return eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
The Swiss legal frame for SME tax return
For an owner in Erlen, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.
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.
Year-end closing: how the mechanics work
The closing is prepared all year long: a monthly bank reconciliation and accruals tracked as you go turn the year-end into a formality, for businesses in Erlen too.
The timetable is tight: accounts drawn up and approved by the general meeting within six months of the year-end. For SME tax return, chasing missing documents from January (bank statements, contracts, insurance settlements) avoids the last-minute sprint and auditor reservations.
Outsource SME tax return 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 SME tax return 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.

A Swiss SME's accounting calendar
January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.
An SME in Erlen that holds its calendar twelve months straight changes its position: fewer official reminders, easier extensions — and SME tax return stops being a source of worry.
Erlen: what changes, what does not
Working with a fiduciary from Erlen no longer depends on geography: the documents of a business in Erlen are shared online, while the canton Thurgau keeps its own deadlines for the tax return.
For a business in Erlen, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Thurgau.
Frequently asked questions
Does MyFiducia.ai work for a business based in Erlen?
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 Erlen manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Erlen: the CO dictates it, not the commune.
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 Erlen as anywhere.
When must a business register for VAT?
As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Erlen as everywhere in Switzerland.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates SME tax return for businesses in Erlen: 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.