UID Checker User Guide – Easily Verify Swiss Business Identifiers

What is the Swiss Business Identifier (UID)?

The UID (Unternehmens-Identifikationsnummer) is a unique identification number assigned by the Swiss Confederation to all legal entities registered in Switzerland – companies, associations, foundations, and more. It is used in all official communications, including tax declarations, VAT returns, commercial register filings, and customs interactions.

The UID consists of the 3‑letter country code “CHE” (Switzerland) followed by 9 digits, making a total of 12 characters. The data carrier is ETC RS2222 FR.

Depending on the language region, the VAT suffix differs: German‑speaking companies use “MWST”, while French‑ and Italian‑speaking ones use “TVA” and “IVA” respectively.

UID Standard and Format Rules

The UID follows the new format standard (E‑Government‑Standard eCH‑0097) introduced by the Swiss Federal Statistical Office in 2011, which completely replaced the old 6‑digit format [reference:0]. The structure is based on the ISO‑Alpha‑3 code “CHE” from ISO 3166‑1, followed by an 8‑digit pseudo‑random number and a single check digit [reference:1].

The standard formatted representation is “CHE‑112.345.678”. On invoices, it is often combined with the VAT suffix, e.g., “CHE‑116.293.044 MWST” [reference:2][reference:3][reference:4].

How to Use This Tool to Verify a Swiss UID?

Just three steps to quickly check whether your UID number is correct:

1. Enter the UID in the input field – either in shorthand like ‘CHE123456789’ or the common format ‘CHE‑123.456.789’.
2. Submit and wait for the validation: the front‑end strips out hyphens and dots, extracts the last 8 digits, and calculates the mod‑11 check digit.
3. Get a clear result displayed right in the middle of the page.

This tool is completely free and ideal for finance staff, tax advisors, and business managers operating in Switzerland.

Frequently Asked Questions

1. Why does the Swiss UID have a check digit?

The UID algorithm follows the eCH‑0097 standard. The first 8 digits are multiplied by specific factors, the sum is taken modulo 11, and that determines the 9th check digit [reference:5]. If the sum is 0 or 1, the check digit is 0; otherwise, it is 11 minus the result of the modulo calculation.

2. Why does my UID appear invalid when I check it with this tool?

Possible reasons: it does not start with ‘CHE’, the last 8 digits fail the mod‑11 validation, or it contains invalid special characters. Please ensure you enter only letters and digits.

3. What is the difference between the UID‑MWST (VAT number) and the plain UID?

The UID is the permanent base identifier for any entity. When a business registers for VAT, the UID gets the suffix MWST/TVA/IVA to serve as the official VAT identification [reference:6]. Always provide the UID‑MWST when required in transactions to comply with Swiss federal tax regulations [reference:7].

If you have further questions, feel free to reach out via the contact information at the bottom of the site. Thank you for using our tool!