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Everything that matters about SME tax return for the self-employed in Basel

SME tax return for the self-employed in Basel 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.

The Swiss legal frame for SME tax return

Three documents summarise the health of a Swiss business: the balance sheet (what it owns), the income statement (what it earns) and the notes (what else you should know). All the work of SME tax return converges on those three pages, in Basel too.

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.

Year-end closing: how the mechanics work

Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.

For SME tax return, the golden rule is to discover nothing in January: every uncertainty (doubtful receivable, dispute, unsellable stock) must be identified before the closing date, not after.

Outsource SME tax return or keep it in-house?

A good test before choosing: ask the fiduciary HOW it wants to receive the documents. A precise answer (formats, frequency, platform) says more than any brochure — including in Basel.

For SME tax return, a quarterly 30-minute check-in with the fiduciary beats an annual marathon: questions get handled while they are small.

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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 Basel) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.

The useful reflex: date every obligation the moment it arises. An employee hired means AHV/LPP deadlines created; VAT registration means a filing cycle set; a closing date fixed means backward planning of the close. Well organised, the SME tax return calendar fills itself.

Basel: what changes, what does not

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

For a business in Basel, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Basel-City.

Frequently asked questions

What is simplified bookkeeping and who can use it?

Sole proprietorships and partnerships under CHF 500,000 of revenue may limit themselves to recording income, expenses and assets (art. 957 para. 2 CO). Once over the threshold — or upon founding a Sàrl or an SA — full accounts with balance sheet, income statement and notes become mandatory. The CHF 500,000 threshold is assessed the same way in Basel.

Does MyFiducia.ai work for a business based in Basel?

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

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 Basel can therefore archive fully digitally.

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

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