Everything that matters about accounts payable for medical practices in Lengnau (AG)
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Lengnau (AG).
The Swiss legal frame for accounts payable
Swiss accounting law has been unified in the Code of Obligations since 2013: the same bookkeeping rules (art. 957a CO) and retention rules (art. 958f CO — 10 years for books, vouchers and reports) apply regardless of legal form. Accounts payable sits squarely within this frame, including for companies based in Lengnau (AG).
For accounts payable, 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.
A Swiss SME's accounting calendar
The professionals' trick: handle every deadline at D-30, not D-1. A VAT return prepared a month early leaves time to chase a missing document without penalty.
Delays rarely come alone: neglected bookkeeping postpones the closing, hence the tax return, hence the recalculated instalments — and the business flies blind for months. Keeping the books current as you go is the only sustainable way to hold every cascading deadline.
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.
Standard numbering also enables automation: stable posting rules (same supplier, same account) make data entry predictable and the audit faster. Avoid changing the chart of accounts mid-year — migrate at the closing date, with a documented mapping table.
Outsource accounts payable or keep it in-house?
Outsourcing accounts payable 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.
A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.
Lengnau (AG): what changes, what does not
Working with a fiduciary from Lengnau (AG) no longer depends on geography: the documents of a business in Lengnau (AG) are shared online, while the canton Aargau keeps its own deadlines for the tax return.
Lengnau (AG) requires no special bookkeeping: the Code of Obligations applies at postal code 5426 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Lengnau (AG) too.
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 Lengnau (AG) as anywhere.
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 Lengnau (AG).
When must a business register for VAT?
As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Lengnau (AG) as everywhere in Switzerland.
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Switch to accounting that keeps itself up to date
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