
Everything that matters about limited statutory audit deadlines in Lengnau (AG)
Delegate, digitalise or do it all yourself? Around limited statutory audit in Lengnau (AG), every SME draws its own line. The reference points below — federal law, cantonal practice and lessons from the field — help you place the cursor well.
Year-end closing: how the mechanics work
The income statement reads as a cascade: gross margin, operating result, financial result, extraordinary result. Each level answers a different question — mixing levels blurs the steering.
A clean closing pays beyond the legal duty: it conditions the tax return, bank discussions and the company's value in a succession. Hidden reserves (accelerated depreciation, provisions) remain admissible within cantonal tax limits — document them systematically.
A well-structured SME chart of accounts
Nearly all Swiss SMEs rely on the standard SME chart of accounts (Sterchi/Käfer): classes 1 (assets) to 9 (closing), with revenue in class 3 and expenses in classes 4 to 6. Using this standard structure makes conversations with your fiduciary, auditor and tax administration far easier.
For limited statutory audit, the right granularity is decisive: enough accounts to steer the business (margins by activity, expenses by nature), few enough that every entry finds its place without hesitation. The VAT accounts (input VAT, VAT due) deserve special care — they are the basis of the annual reconciliation.
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 Lengnau (AG)) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.
For limited statutory audit, deadline discipline is worth real money: default interest on late VAT, AHV adjustments, tax fines. A shared deadline calendar — fed by up-to-date figures — remains the simplest safeguard.

Outsource limited statutory audit or keep it in-house?
A good test before choosing: ask the fiduciary HOW it wants to receive the documents. A precise answer (formats, frequency, platform) says more than any brochure — including in Lengnau (AG).
A business in Lengnau (AG) can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — limited statutory audit splits very well.
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
How much does limited statutory audit cost in Lengnau (AG)?
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.
How long must records related to limited statutory audit 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 Lengnau (AG) can therefore archive fully digitally.
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.
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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