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Withholding tax for construction companies in Solothurn: the practical guide

Withholding tax for construction companies in Solothurn 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 withholding tax

AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Solothurn with a clean audit trail sails through these exercises.

The good news: the Swiss frame is stable and predictable. Structure withholding tax once — chart of accounts, document flow, calendar — and the same organisation pays off for years.

Salaries and social contributions: the rates to know

Absences are managed upstream: illness, accident, military service or maternity trigger allowances (APG, insurance) that replace part of the salary. Clean absence records are the basis of correct settlements, in Solothurn as elsewhere.

A thirteenth salary, where agreed, is accrued month by month — forget it and December reveals a charge of one-twelfth of the payroll, in Solothurn as everywhere.

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

An SME in Solothurn that holds its calendar twelve months straight changes its position: fewer official reminders, easier extensions — and withholding tax stops being a source of worry.

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Outsource withholding tax 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.

A business in Solothurn is no longer limited to fiduciaries in its canton: with a shared online platform, collaboration works remotely, documents and entries visible to both sides in real time. The choice widens to all of Switzerland — competence becomes the criterion again, not the postcode.

Solothurn: what changes, what does not

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

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 current Swiss VAT rates?

Since 1 January 2024: 8.1% (standard), 2.6% (reduced — for example food and medicines) and 3.8% (accommodation). Returns must be filed and paid within 60 days after the period ends (quarterly under the effective method, semi-annually under the net tax rate method). These federal rates apply unchanged in Solothurn.

What are the legal obligations for withholding tax 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 withholding tax 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.

Do you need a fiduciary for withholding tax, 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 Solothurn.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates withholding tax 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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