Pen pointing at a bar chart on paper

Bookkeeping for construction companies in Sins explained simply

Bookkeeping for construction companies in Sins rests on three pillars: federal law that applies across Switzerland, cantonal deadlines worth knowing, and tools that eliminate re-keying. This guide puts it all in order, fact by fact.

The Swiss legal frame for bookkeeping

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

For bookkeeping, 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.

Digitalising bookkeeping: what actually works

Accounting digitalisation always follows the same path: capture documents at the source (photo or PDF upload), let automatic recognition extract supplier, amount, date and VAT, approve the proposed entries, then archive each document linked to its entry. Every step removes a re-keying — and therefore an error source.

The winning pair for bookkeeping: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.

A Swiss SME's accounting calendar

Tax instalments are steered: too low, they set up a salty final bill; too high, they tie up cash. Adjusting them on current figures is a profitable reflex, in Sins as anywhere.

For bookkeeping, year-end is prepared in October: last invoices, investment decisions, provisions to assess — December is too late to act, January is for recording.

Pen pointing at a bar chart on paper

A well-structured SME chart of accounts

Shareholder current accounts demand strict hygiene: every private withdrawal documented, interest at the rates accepted by the tax administration, and a clean-up at closing.

Suspense accounts (to clarify) are useful provided they are emptied monthly: a swelling “miscellaneous” account is the classic symptom of a chart that no longer fits the activity.

Sins: what changes, what does not

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

Sins requires no special bookkeeping: the Code of Obligations applies at postal code 5643 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 bookkeeping, 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 Sins.

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 Sins as anywhere.

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 Sins, family allowances follow the canton's rates.

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 Sins as anywhere.

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Switch to accounting that keeps itself up to date

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

The application is operated in French.

    Bookkeeping for construction companies in Sins — Swiss guide