
Sole proprietorship for construction companies in Rümlingen: what every SME should know
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on sole proprietorship in Rümlingen: what the law requires, what can be automated, and when to delegate.
Choosing the structure: Sàrl, SA or sole proprietorship
Check the company name before any enthusiasm: availability in the commercial register, internet domain, possible trademark. Renaming later costs time and trust, in Rümlingen as elsewhere.
Settling in Rümlingen also means thinking about insurance from incorporation: professional liability, property, business interruption — the accounts keep track of them and the closing allocates them correctly.
Swiss VAT: rates, threshold and filings
Three rates coexist in Switzerland: 8.1% for most supplies, 2.6% for everyday essentials and 3.8% for accommodation. Businesses staying under CHF 100,000 a year are exempt from registration but may opt in voluntarily — useful to reclaim input VAT on investments.
Also useful for sole proprietorship: some supplies are excluded from VAT (health, education, property rental) — with no corresponding input VAT right. Qualifying revenues correctly from the start avoids surprises.
Salaries and social contributions: the rates to know
The salary certificate is an official tax document: it feeds the employee's tax return and serves as the reference in AHV and tax audits. Issued once a year, it must match payroll accounting and the declaration to the compensation office to the centime.
For sole proprietorship, the monthly payslip is only the visible part: instalments to the funds, annual settlements and certificates form the real cycle, January to January.

The Swiss legal frame for sole proprietorship
A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Rümlingen as anywhere.
The good news: the Swiss frame is stable and predictable. Structure sole proprietorship once — chart of accounts, document flow, calendar — and the same organisation pays off for years.
Rümlingen: what changes, what does not
Working with a fiduciary from Rümlingen no longer depends on geography: the documents of a business in Rümlingen are shared online, while the canton Basel-Country keeps its own deadlines for the tax return.
Rümlingen requires no special bookkeeping: the Code of Obligations applies at postal code 4444 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
Do you need a fiduciary for sole proprietorship, 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 Rümlingen.
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 Rümlingen: 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 Rümlingen, family allowances follow the canton's rates.
Effective VAT method or net tax rate: how to choose?
The effective method deducts actual input VAT and files quarterly; the net tax rate method applies a flat industry rate to turnover, semi-annually, with no separate input VAT deduction. The flat rate suits low-cost structures; as investments grow, the effective method usually wins again. The choice rests on the company's own figures, in Rümlingen as anywhere.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates sole proprietorship for businesses in Rümlingen: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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