Bookkeeping obligations affect almost every business in Switzerland, but not all in the same way. An AG must keep double-entry books and prepare financial reports; a small sole proprietor may limit records to income, expenses and financial position. There are also rules on how to keep books and how long to retain vouchers. This guide explains bookkeeping obligations for SMEs under the Code of Obligations (CO, OR) and the Ordinance on Accounting Records (GeBüV), and shows what to watch for in everyday work.
Who must keep books
Art. 957 CO governs the duty to keep accounts and prepare financial reports. Para. 1 names two groups:
- Sole proprietorships and partnerships with sales revenue of at least 500’000 francs in the previous financial year,
- Legal entities, for example an AG or GmbH.
Under para. 2, only income, expenses and financial position need to be recorded by: sole proprietorships and partnerships with sales revenue below 500’000 francs in the previous financial year, associations and foundations not required to be entered in the commercial register, and foundations exempt from the duty to appoint an auditor. The principles of proper bookkeeping apply to them by analogy (para. 3).
| Business | Obligation under Art. 957 CO |
|---|---|
| Other legal entities (except para. 2), including small AGs and GmbHs | Bookkeeping and financial reporting |
| Sole proprietorship, partnership with sales revenue of at least 500’000 francs in the previous financial year | Bookkeeping and financial reporting |
| Sole proprietorship, partnership with sales revenue below 500’000 francs | Income, expenses and financial position |
| Associations and foundations not required to register | Income, expenses and financial position |
The law refers to the “previous financial year”. If in doubt about exactly when a company crosses the threshold, clarify this with your fiduciary.
What proper bookkeeping requires
Under Art. 957a CO, bookkeeping forms the basis of financial reporting. It follows the principles of proper bookkeeping. In particular, these require:
- Complete, truthful and systematic recording of business transactions,
- Documentary evidence for individual postings,
- Clarity,
- Appropriateness to the nature and size of the business,
- Verifiability.
An accounting voucher is any written record on paper or in electronic or comparable form needed to trace a business transaction. Books are kept in the national currency or the currency essential to the business activity, in a national language or English, and may be maintained in writing, electronically or in a comparable manner.
General ledger, journal and subsidiary ledgers
The Ordinance on Accounting Records determines which books must be kept. Under Art. 1 GeBüV, anyone required to keep accounts needs a general ledger and, depending on the nature and scale of the business, subsidiary ledgers. The general ledger consists of the accounts, meaning the logical classification of all posted business transactions, and the journal, the chronological recording of all posted business transactions. The ordinance specifically names payroll accounting, accounts receivable and payable, and ongoing records of inventories or unbilled services as subsidiary ledgers.
Unaltered and traceable: the integrity of the books
The GeBüV sets out how books must be kept and retained:
- Integrity (Art. 3): Accounting records and vouchers must be kept and retained so they cannot be changed without the change being detectable. The ordinance therefore requires changes to be detectable.
- Documentation (Art. 4): Depending on the nature and scale of the business, organisation, responsibilities, workflows and procedures, and infrastructure (machines and programs) must be documented in work instructions so that books and vouchers can be understood. Work instructions must be updated and retained for as long as the books.
- Availability (Art. 6): Until the retention period ends, an authorised person must be able to inspect and check books and vouchers within a reasonable time. On request, accounting records must also be made readable without auxiliary equipment.
- Storage media (Art. 9): Unalterable media such as paper are permitted. Alterable media, such as hard drives, are permitted only if procedures ensure integrity (digital signature procedures are given as an example), the storage time can be proved without falsification (example: timestamps), other requirements are met and processes are documented, including protocols and log files.
- Checking and migration (Art. 10): Storage media must be checked regularly for integrity and readability; data migration must preserve completeness, accuracy and readability, and the transfer must be logged.
Annual report and deadlines
Anyone required to prepare financial reports produces an annual report (Art. 958 CO, para. 2). It contains the annual financial statements: balance sheet, income statement and notes. Sole proprietorships and partnerships not required to report under the rules for larger companies may omit the notes. Additional information required by the minimum presentation rules must then appear directly in the balance sheet or income statement (Art. 959c CO, para. 3). The annual report must be prepared within six months after the financial year ends and submitted to the competent body for approval. It is signed by the chair of the highest management or governing body and the person responsible for financial reporting (para. 3). Rules for larger companies and groups remain reserved and are not covered here.
Art. 958b CO, para. 2 provides relief for small businesses: if net proceeds from goods and services or financial income do not exceed 100’000 francs, the requirement to allocate expenses and income to the appropriate period may be waived, and accounting may instead be based on cash payments and receipts.
Retention: ten years and exceptions
Art. 958f CO, para. 1 requires accounting records, vouchers, the annual report and audit report to be retained for ten years. The period starts at the end of the financial year. The annual report and audit report must be retained in writing and signed (para. 2). Books and vouchers may also be retained electronically if correspondence with the business transactions is ensured and they can be made readable again at any time (para. 3).
Anyone liable for VAT must retain accounting records, vouchers and other records until the tax claim reaches its absolute limitation period under Art. 70 of the Federal Act on Value Added Tax (VAT Act, MWSTG), para. 2; Art. 958f CO remains reserved. Documents used to calculate subsequent input tax deduction and own consumption for immovable property have a 20-year retention period (Art. 70, para. 3). Under Art. 42 VAT Act (MWSTG), para. 6, absolute limitation occurs ten years after the end of the tax period.
Practical example: Schreinerei Muster
Schreinerei Muster is a fictional sole proprietorship. Its sales revenue was CHF 462’000.00 in 2025 and CHF 531’000.00 in 2026. Under the wording of Art. 957 CO, sales revenue from the previous financial year is decisive. For 2026, 2025 counts with CHF 462’000.00, below 500’000 francs: the owner falls under para. 2, keeps records of income, expenses and financial position and need not prepare an annual report. For 2027, 2026 counts with CHF 531’000.00, at least 500’000 francs. The difference from the threshold is 531’000 − 500’000 = CHF 31’000.00. From 2027, the joinery falls under para. 1, keeps double-entry books and for the first time prepares a balance sheet and income statement in its annual report for financial year 2027; notes are needed only if the exception under Art. 959c CO, para. 3 does not apply. Under Art. 958, para. 3, it must be prepared within six months after the financial year ends, meaning by 30 June 2028.
The “change nothing” rule appears in everyday work: in March 2027, the joinery accidentally posts a supplier invoice of CHF 2’540.00 as CHF 2’450.00 (transposed digits). It does not delete the posting; it reverses it with a counter-entry of CHF 2’450.00 referring to the original, then re-enters the invoice as CHF 2’540.00. The CHF 90.00 difference is traceable in the journal and the original remains visible.
Financial year 2027 ends on 31 December 2027. Under Art. 958f CO, the joinery retains that year’s vouchers for ten years, until the end of 2037.
Checklist
- Legal form and previous financial year’s sales revenue checked: double-entry or simple bookkeeping
- General ledger (accounts and journal) maintained, subsidiary ledgers available as appropriate
- A voucher for every posting
- Corrections through counter-entries, no deletion
- Work instructions for organisation, workflows and programs documented and current
- Books and vouchers always retrievable and readable
- Storage media checked regularly, data migration logged
- Annual report prepared within six months, annual report and audit report retained with signatures
- Retention: ten years after the end of the financial year, Art. 70 VAT Act (MWSTG) observed if liable for VAT
How KMU | base helps
Finance | base maintains the journal so changes remain visible and separates simple from double-entry bookkeeping per company. Overall compliance of your bookkeeping remains the responsibility of those in charge of the business; the software supports them.
1. Choose simple or double-entry. Finance | base offers simple bookkeeping under Art. 957 CO, para. 2 per company (intended for sole proprietorships, associations and micro businesses): record income, expenses and transfers between cash and bank with a category and voucher, and the counter-entry is created automatically in the journal. Whether you may legally use it is determined by Art. 957 CO: it applies to sole proprietorships and partnerships with sales revenue below 500’000 francs in the previous financial year, associations and foundations not required to register in the commercial register, and foundations exempt from appointing an auditor. Small AGs and GmbHs always fall under para. 1. Later, a guided process lets you switch to double-entry bookkeeping; all postings and vouchers remain unchanged in the journal.
2. Consecutively numbered and chained. Each posting receives an unbroken sequential number per company, even with simultaneous postings. Each posting is chained to the previous one. Every time you open Finance › Accounting › Journal, the page shows whether all postings are unchanged or identifies the first altered one.
3. Correct through reversal. Correct using a counter-entry with a reference; the original remains visible and any associated incoming voucher is released for processing again.
4. Lock months. Under Finance › Accounting › Closing, lock checked months; this is irreversible, and earlier open months in the same financial year are locked too. Locked months and closed years accept no more postings; a reversal into such a period is posted to today. Before year-end closing, reconciliation shows, among other things, how many postings lack a voucher.
5. Retain records. In Docu | base, each document version becomes its own immutable archive entry; corrections are created only as new versions referring to the original. Each document has a retention class with a period and legal basis, for example ten years after financial year-end or 20 years for VAT documents relating to property. Complete the procedural documentation under Art. 4 GeBüV there yourself: save versions with validity dates and download them as PDFs; the operator’s section is included.
To try it yourself, view the demo or open a trial account. Income-and-expense accounting or double-entry bookkeeping? helps with the choice of bookkeeping type, and Chart of accounts for SMEs with account structure. For questions, use our Contact page.
Sources
- Code of Obligations (CO, OR, SR 220), Art. 957, paras. 1–3, Art. 957a, Art. 958, paras. 2 and 3, Art. 958b, para. 2, Art. 959c, para. 3, Art. 958f, paras. 1–3, as at 1 October 2026: fedlex.admin.ch (German original), accessed on 26.10.2026.
- Ordinance on the Keeping and Retention of Accounting Records (Ordinance on Accounting Records, GeBüV, SR 221.431), Art. 1, 3, 4, 6, 9 and 10, as at 1 January 2013 (version available on Fedlex on 26.10.2026): fedlex.admin.ch (German original), accessed on 26.10.2026.
- Federal Act on Value Added Tax (VAT Act, MWSTG, SR 641.20), Art. 42, para. 6 and Art. 70, paras. 2 and 3, as at 1 January 2025: fedlex.admin.ch (German original), accessed on 26.10.2026.
This guide does not replace legal or tax advice. Information as at 26 October 2026.