
Fiduciary services comparison in Aarburg: 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 Aarburg: what the law requires, what can be automated, and when to delegate.
The Swiss legal frame for fiduciary services
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 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.
A Swiss SME's accounting calendar
The typical annual cycle: monthly or quarterly AHV instalments, VAT returns (quarterly under the effective method, semi-annual under the net tax rate), the final salary declaration in January, closing in the first half-year, then the tax return and the annual VAT reconciliation. Each link depends on the quality of the previous one.
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 fiduciary services or keep it in-house?
Outsourcing fiduciary services 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 business in Aarburg can combine the models: internal day-to-day entry, monthly external supervision, closing and taxes with the specialist — fiduciary services splits very well.

Digitalising fiduciary services: what actually works
Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.
The winning pair for fiduciary services: a single inbox (e-mail, scan, photo) and one simple rule — no document sits more than a few days without a proposed entry.
Aarburg: what changes, what does not
Working with a fiduciary from Aarburg no longer depends on geography: the documents of a business in Aarburg are shared online, while the canton Aargau keeps its own deadlines for the tax return.
For a business in Aarburg, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.
Frequently asked questions
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 Aarburg: the CO dictates it, not the commune.
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 Aarburg too.
Do you need a fiduciary for fiduciary services, or can you do it yourself?
Both are defensible. Below CHF 500,000 of revenue, a sole proprietorship may keep simplified accounts itself. As soon as payroll, VAT and a closing with tax stakes are involved, professional support prevents mistakes that cost more than the fees. With a shared platform, the fiduciary does not even need to be in Aarburg.
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 Aarburg as anywhere.
Also worth reading
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Switch to accounting that keeps itself up to date
MyFiducia.ai automates fiduciary services for businesses in Aarburg: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
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