
Fiduciary services paperless in Sins: rules, deadlines, best practice
Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on fiduciary services in Sins: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for fiduciary services
Whether a business sits in Sins or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for fiduciary services. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
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 Sins as anywhere.
The timetable is tight: accounts drawn up and approved by the general meeting within six months of the year-end. For fiduciary services, chasing missing documents from January (bank statements, contracts, insurance settlements) avoids the last-minute sprint and auditor reservations.
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 Sins) 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.

Outsource fiduciary services or keep it in-house?
Responsibility stays with the client: the fiduciary executes with care, but the signed accounts bind the company. Understanding what you sign is not optional.
Three signals say it is time to delegate more: missed deadlines (VAT, AHV), entries running months behind, or an owner spending evenings on receipts instead of the business. Conversely, an SME equipped with modern software can safely take day-to-day entry back in-house.
Sins: what changes, what does not
Working with a fiduciary from Sins no longer depends on geography: the documents of a business in Sins are shared online, while the canton Aargau keeps its own deadlines for the tax return.
Federal deadlines do not move in Sins: VAT within 60 days, salary declaration in January, 10-year record retention — postal code 5643 changes nothing about those rules, only the sender's address.
Frequently asked questions
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.
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.
Does MyFiducia.ai work for a business based in Sins?
Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Sins manages its documents, VAT and exports exactly as anywhere in Switzerland.
How long must records related to fiduciary services 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 Sins can therefore archive fully digitally.
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Switch to accounting that keeps itself up to date
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