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Limited statutory audit for architecture firms in Lenzburg: rules, deadlines, best practice

Whether you run a Sàrl, an SA or a sole proprietorship in Lenzburg, limited statutory audit eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.

Year-end closing: how the mechanics work

The order of operations matters: reconciliations first (bank, cash, receivables, payables), then the closing entries, finally the VAT and AHV consistency checks. Reversing the order means starting over.

For limited statutory audit, 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.

A Swiss SME's accounting calendar

Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.

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.

Outsource limited statutory audit or keep it in-house?

A fiduciary's cost depends first on the quality of the data received: digitised, filed, reconciled documents are processed fast; a box of loose receipts is billed by the hour. Improving the internal preparation of limited statutory audit lowers fees more surely than any negotiation.

A business in Lenzburg can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — limited statutory audit splits very well.

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The Swiss legal frame for limited statutory audit

In Switzerland, the duty to keep accounts stems from art. 957 ff. of the Code of Obligations. Legal entities (Sàrl, SA) and sole proprietorships with at least CHF 500,000 in revenue keep full accounts: balance sheet, income statement and notes. Below that threshold, a simplified record of income, expenses and assets is sufficient.

Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For limited statutory audit, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.

Lenzburg: what changes, what does not

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

Federal deadlines do not move in Lenzburg: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5600 changes nothing about those rules, only the sender's address.

Frequently asked questions

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 Lenzburg as everywhere 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 Lenzburg: the CO dictates it, not the commune.

How much does limited statutory audit cost in Lenzburg?

It depends on document volume, the number of salaries and VAT complexity — no serious figure can be quoted without examining the file. Two levers cut the bill everywhere: digitised, well-filed receipts and software that prepares entries instead of having them re-keyed.

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 Lenzburg, family allowances follow the canton's rates.

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Switch to accounting that keeps itself up to date

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    Limited statutory audit for architecture firms in Lenzburg