
Annual closing required documents in Solothurn without the stress: how it works
Whether you run a Sàrl, an SA or a sole proprietorship in Solothurn, annual closing eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
Year-end closing: how the mechanics work
Depreciation follows rates accepted by tax practice (property, machinery, IT): staying within those ranges avoids reassessments. Exceeding them is justified — and documented, in Solothurn as anywhere.
For an SME in Solothurn, the closing is also decision time: distributions, provisions, investments to anticipate. A file ready in February leaves time to decide; one ready in June just endures.
Outsource annual closing or keep it in-house?
Outsourcing annual closing 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.
For annual closing, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.
The Swiss legal frame for annual closing
For an owner in Solothurn, 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.
One simple principle drives annual closing: 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.

A Swiss SME's accounting calendar
Every deadline has an owner: an obligation “of everyone” is kept by no one. Naming one person per deadline family (VAT, payroll, taxes) closes the gaps.
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.
Solothurn: what changes, what does not
Working with a fiduciary from Solothurn no longer depends on geography: the documents of a business in Solothurn are shared online, while the canton Solothurn keeps its own deadlines for the tax return.
Federal deadlines do not move in Solothurn: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 4500 changes nothing about those rules, only the sender's address.
Frequently asked questions
What are the legal obligations for annual closing 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 Solothurn: federal law applies.
How long must records related to annual closing 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 Solothurn can therefore archive fully digitally.
What is the difference between a limited and an ordinary audit?
The ordinary audit applies to companies exceeding, for two consecutive years, two of three thresholds: CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions. Others fall under the limited audit, and those with no more than ten full-time positions on annual average can opt out with all shareholders' consent. These federal thresholds do not depend on the registered seat — in Solothurn as anywhere.
When is entry in the commercial register mandatory?
A Sàrl and an SA only come into existence with their registration. A sole proprietorship must register from CHF 100,000 of annual revenue; below that, registration stays voluntary but adds credibility and protects the business name. Registration goes through the canton's commercial register office — for Solothurn too.
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MyFiducia.ai automates annual closing for businesses in Solothurn: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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