
Balance sheet preparation for construction companies in Arni (AG): rules, deadlines, best practice
Swiss accounting law (art. 957 ff. of the Code of Obligations) sets a precise frame, yet day-to-day practice often stays fuzzy. This guide walks through what actually matters for a business based in Arni (AG).
Year-end closing: how the mechanics work
Accrual accounting is the technical heart of the closing: every income and every expense belongs to the year it economically concerns, regardless of the payment date. Rents paid in advance, insurance premiums straddling the date, supplier invoices arriving in January: all flow through accrual accounts.
For an SME in Arni (AG), the closing is also decision time: distributions, provisions, investments to anticipate. A file ready in February leaves time to decide; one ready in June just endures.
Outsource balance sheet preparation or keep it in-house?
Splitting roles clearly avoids duplication: the company captures documents and approves payments; the fiduciary checks postings, closes the year and defends the file before the authorities. Each side does what it does best — and nobody keys the same invoice twice.
A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.
The Swiss legal frame for balance sheet preparation
Three documents summarise the health of a Swiss business: the balance sheet (what it owns), the income statement (what it earns) and the notes (what else you should know). All the work of balance sheet preparation converges on those three pages, in Arni (AG) too.
The annual accounts (art. 958 CO) consist of the balance sheet, the income statement and the notes; they must be drawn up within six months of the year-end so the general meeting can approve them. A delay here cascades into the tax return and the final social insurance settlements.

A Swiss SME's accounting calendar
Every deadline has an owner: an obligation “of everyone” is kept by no one. Naming one person per deadline family (VAT, payroll, taxes) closes the gaps.
For balance sheet preparation, 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.
Arni (AG): what changes, what does not
Working with a fiduciary from Arni (AG) no longer depends on geography: the documents of a business in Arni (AG) are shared online, while the canton Aargau keeps its own deadlines for the tax return.
Federal deadlines do not move in Arni (AG): VAT within 60 days, salary declaration in January, 10-year record retention — postal code 8905 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 Arni (AG) as anywhere.
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 Arni (AG).
Do you need a fiduciary for balance sheet preparation, 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 Arni (AG).
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 Arni (AG) as everywhere in Switzerland.
Also worth reading
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Switch to accounting that keeps itself up to date
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