
Accounting outsourcing for law firms in Arbon: 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 Arbon.
The Swiss legal frame for accounting outsourcing
Whether a business sits in Arbon or elsewhere in Switzerland, the same federal law applies — one of the strengths of the Swiss system for accounting outsourcing. Cantonal differences concentrate on taxation (rates, filing deadlines); bookkeeping itself follows art. 957 ff. CO everywhere.
Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.
A Swiss SME's accounting calendar
January: salary declaration to the compensation office and salary certificates. End of February, May, August, November: quarterly VAT returns (effective method), each to be filed and paid within 60 days after the quarter ends. Within six months of year-end: approved annual accounts. Then: the tax return under cantonal deadlines, with extensions possible.
For accounting outsourcing, 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 accounting outsourcing or keep it in-house?
Outsourcing does not exempt you from understanding: an owner who can read the balance sheet and the income statement challenges the fiduciary better — and pays for advice, not re-keying.
For accounting outsourcing, the internal-external duo works when both sides see the same file: same entries, same documents, same deadlines. Misunderstandings are born from parallel copies.

Year-end closing: how the mechanics work
Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.
The notes complete the figures: valuation principles, liabilities towards pension institutions, contingent liabilities, or the number of full-time positions. Careful notes reduce questions from the auditor and the banks.
Arbon: what changes, what does not
Working with a fiduciary from Arbon no longer depends on geography: the documents of a business in Arbon are shared online, while the canton Thurgau keeps its own deadlines for the tax return.
Arbon requires no special bookkeeping: the Code of Obligations applies at postal code 9320 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.
Frequently asked questions
How long must records related to accounting outsourcing 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 Arbon can therefore archive fully digitally.
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 Arbon: the CO dictates it, not the commune.
Does MyFiducia.ai work for a business based in Arbon?
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 Arbon manages its documents, VAT and exports exactly as anywhere in Switzerland.
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 Arbon as anywhere.
Also worth reading
In neighbouring municipalities
Switch to accounting that keeps itself up to date
MyFiducia.ai automates accounting outsourcing for businesses in Arbon: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.
The application is operated in French.