
Fiduciary services for SMEs in Lenzburg: the practical guide
Whether you run a Sàrl, an SA or a sole proprietorship in Lenzburg, fiduciary services eventually lands on your desk. Here are the practical reference points — legal basis, deadlines and common pitfalls — to decide with a clear head.
The Swiss legal frame for fiduciary services
AHV audits and VAT audits follow the same logic: start from the documents, trace to the entries, check consistency. A business in Lenzburg with a clean audit trail sails through these exercises.
Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For fiduciary services, 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.
Year-end closing: how the mechanics work
Depreciation follows rates accepted by tax practice (property, machinery, IT): staying within those ranges avoids reassessments. Exceeding them is justified — and documented, in Lenzburg as anywhere.
A well-ordered closing file speeds everything up: bank statements at the closing date, a signed inventory, final AHV/LPP/accident settlements, new or amended contracts, and support for the accruals. Fiduciary services in Lenzburg then finishes in days, not weeks.
Digitalising fiduciary services: 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.
For fiduciary services, migrating history must not block the start: begin on day one of the current financial year and import the history later if needed.

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 Lenzburg) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.
For fiduciary services, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.
Lenzburg: what changes, what does not
Lenzburg (postal code 5600, canton Aargau) applies the same federal rules as the rest of the country: what changes in Lenzburg are the cantonal counterparts — tax administration, compensation office, commercial register.
Lenzburg requires no special bookkeeping: the Code of Obligations applies at postal code 5600 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
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 Lenzburg.
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 Lenzburg 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 Lenzburg as anywhere.
Can fiduciary services be automated with AI?
Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches fiduciary services.
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MyFiducia.ai automates fiduciary services for businesses in Lenzburg: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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