UID and VAT number checkerOne less typo on your invoices
Check the format and check digit of a CHE number before saving it for a supplier or printing it on an invoice.
- Free
- No sign-up
- Nothing is stored
The registers are the reference. The format and the check digit are verified in your browser; the company status and the VAT registration are read from the federal registers (Zefix, UID register of the FSO) at the moment of the check. The registers remain the legal reference.
Enter a number, for example CHE-123.456.788. The check runs in your browser.
Once the check digit is right, the number is looked up in the commercial register and in the VAT register below. The official sites remain the reference.
Check a list of numbers
One number per line, up to 200 lines. Nothing is sent.
One wrong digit in a UID number is enough to block a VAT filing
The business identification number, CHE followed by nine digits, identifies every Swiss company, and its suffix MWST, TVA or IVA signals VAT liability. A typo on a supplier invoice is invisible to the eye, and it can get an input tax deduction refused months later. The last digit of the number is a check digit: this checker recalculates it in an instant and tells you whether the entry is possible.
How the check works
1
The format
The number has the letters CHE and nine digits, with or without hyphens and dots, and possibly a suffix MWST, TVA or IVA.
2
The check digit
The first eight digits are multiplied by weights of 5, 4, 3, 2, 7, 6, 5 and 4, added up, and the remainder of the division by 11 gives the check digit. The ninth digit must equal it.
3
What the check does not tell you
A well-formed number is then looked up in the federal registers: the commercial register says whether the company is active, the UID register whether it is VAT-registered.
A concrete example
CHE-123.456.788 is well formed: the weighted sum of the first eight digits is 168, the remainder of the division by 11 is 3, and the check digit is therefore 8. CHE-123.456.789 is rejected for the same reason, because its last digit should be 8.
The most common mistakes
- Swapping two digits when copying a number: the check digit is designed to catch it, but only if you check it.
- Taking a well-formed number as proof of VAT liability: read the VAT status from the register, as the checker does.
What changes in 2026
The format of the UID number has not changed: three letters and nine digits, with a language-dependent suffix for VAT. The format check comes first, then the lookup in the registers.
Frequently asked questions about the UID number
What is the difference between the UID number and the VAT number?
The VAT number is the UID number followed by the suffix MWST, TVA or IVA. The nine digits are the same.
Does this checker confirm that the company exists?
Yes, for a number whose check digit is right: it reads the commercial register (active, being wound up, deleted) and the VAT register (registered, since when) live. A company that is not in the commercial register can still have a UID.
Can I check several numbers at once?
Yes. Open the "Check a list of numbers" section, paste one number per line and export the result as CSV.
Are my numbers sent to a server?
No. The check is calculated in your browser. No number is transmitted or stored.
Why can a number have a correct format but a wrong check digit?
It is a sign of a typo, because the check digit depends on the other eight digits. Check what you entered digit by digit.
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E-mail alerts
Get told when these figures change
VAT rates, contributions, tariffs: one e-mail the day a figure in this calculator moves, not one more. Nothing is sent before you confirm.
For fiduciaries
Give this calculator to your clients
Paste this code on your website. The calculator shows up as is, free, with no sign-up for your visitors.
Clean supplier data from the start
Contacts, UID and VAT numbers checked on entry, then carried into every invoice and every VAT return.
The Starter plan is free and carries no commitment. A fiduciary firm from the directory can also take over the file with you.