Handshake during a business meeting, top view

SME tax return for architecture firms in Wettingen: rules, deadlines, best practice

Delegate, digitalise or do it all yourself? Around SME tax return in Wettingen, 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.

The Swiss legal frame for SME tax return

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. SME tax return sits squarely within this frame, including for companies based in Wettingen.

The law also settles the form: accounts may be kept in a national language or in English, on paper or electronically (art. 957a para. 5 CO). That pragmatism lets SME tax return run entirely on digital tools — no paper binder is required.

Swiss VAT: rates, threshold and filings

A VAT return is prepared, not endured: clean VAT accounts, one code per rate and a monthly variance check make the deadline trivial — for registered businesses in Wettingen too.

For an SME in Wettingen, electronic filing of VAT returns has been mandatory since 1 January 2025; the tax administration's online portal is also where extensions are requested and past periods consulted. Combined with accounts that prepare the return automatically, SME tax return stops being a quarterly chore.

Outsource SME tax return or keep it in-house?

Outsourcing SME tax return to a fiduciary frees up time and secures compliance; keeping it in-house preserves a continuous view and costs less in fees. The best answer is often hybrid: the company captures and digitises as it goes, the fiduciary supervises, closes the books and represents the company before the authorities.

Three signals say it is time to delegate more: missed deadlines (VAT, AHV), entries running months behind, or an owner spending evenings on receipts instead of the business. Conversely, an SME equipped with modern software can safely take day-to-day entry back in-house.

Team analysing financial charts around a table

A Swiss SME's accounting calendar

Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.

Handing deadline monitoring to a tool is no luxury: automatic reminders, a status per obligation, and an “all green” view that clears the mind. What matters is not who ticks the box — but that the box exists and everyone can see it.

Wettingen: what changes, what does not

Sole proprietorship, Sàrl or SA in Wettingen: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.

Wettingen requires no special bookkeeping: the Code of Obligations applies at postal code 5430 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

How long must records related to SME tax return 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 Wettingen can therefore archive fully digitally.

Do you need a fiduciary for SME tax return, 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 Wettingen.

What are the legal obligations for SME tax return 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 Wettingen: 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 Wettingen: the CO dictates it, not the commune.

Also worth reading

In neighbouring municipalities

Switch to accounting that keeps itself up to date

MyFiducia.ai automates SME tax return for businesses in Wettingen: 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.