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SME tax return for architecture firms in Olten: the practical guide

Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on SME tax return in Olten: what the law requires, what can be automated, and when to delegate.

The Swiss legal frame for SME tax return

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 Olten.

For SME tax return, the classic early mistake remains mixing private and business: a dedicated bank account and documented private withdrawals eliminate half the discussions with the tax office.

A Swiss SME's accounting calendar

Three families of deadlines shape the year: federal (VAT within 60 days, salary declaration in January), cantonal (tax return, extensions depending on the canton, including in Olten) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.

For SME tax return, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.

Year-end closing: how the mechanics work

The CO's accounting principles frame the closing: regularity, prudence and consistency of presentation (art. 958c CO), on the going-concern assumption (art. 958a CO). In practice, that means valuation methods kept constant from one year to the next — and documented whenever they change.

For SME tax return, a closing checklist reused every year transforms the exercise: same steps, same checks, same documents — only the year changes.

Team analysing financial charts around a table

Outsource SME tax return or keep it in-house?

The Swiss fiduciary market is dense and governed by professional practice: industry standards, business secrecy, civil liability. Compare offers on three concrete criteria — exact scope (data entry? closing? payroll? VAT?), a named contact person, and the tools used. It prevents year-end misunderstandings.

Changing fiduciary is not a drama: the accounting data belongs to the company, and a clean export (entries, chart of accounts, linked documents) allows a transition at year-end. A provider who locks in a client's data says a lot about how it works.

Olten: what changes, what does not

Working with a fiduciary from Olten no longer depends on geography: the documents of a business in Olten are shared online, while the canton Solothurn keeps its own deadlines for the tax return.

Olten requires no special bookkeeping: the Code of Obligations applies at postal code 4600 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

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 Olten: 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 Olten: the CO dictates it, not the commune.

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 Olten, family allowances follow the canton's rates.

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 Olten can therefore archive fully digitally.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates SME tax return for businesses in Olten: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

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