Free calculator
Tax ID validator: EIN, RFC, RUC, RUT and NIT
Check that a tax ID is written correctly before you put it on an invoice: a U.S. EIN, a Mexican RFC, a Peruvian or Ecuadorian RUC, a Chilean RUT or a Colombian NIT. The tool validates the format and the check digit.
What you type is calculated in your browser and is not sent or saved. Results are for reference and do not replace the advice of an accountant or a lawyer.
How to use the validator
- Choose the country and, where there is more than one, the type of ID.
- Type or paste the number. Dots, dashes and spaces are ignored.
- If the number is valid you see it written in its usual format. If it is not, you see what is wrong.
Everything is checked in your browser: the number you type is not sent or stored.
What this tool checks (and what it does not)
The validator checks that the number has the right shape: the number of digits or characters, the date inside an RFC, and the check digit where the ID has one. A number can pass these checks and still not belong to anyone.
It does not confirm that the number is registered, active or that it belongs to the name on your invoice. For that, use the tax authority's own lookup, or ask your customer or supplier for their registration certificate.
ID formats by country
| Country | ID | Format | Check digit |
|---|---|---|---|
| United States | EIN | 9 digits, written XX-XXXXXXX | No (the prefix must be one the IRS assigns) |
| Mexico | RFC | 12 characters (legal entities) or 13 (individuals) | Yes, one character |
| Peru | RUC | 11 digits, starting with 10, 15, 16, 17 or 20 | Yes, the last digit |
| Chile | RUT | Digits plus a check digit (0–9 or K), written 12.345.678-5 | Yes |
| Ecuador | RUC | 13 digits: an ID or company number followed by 001 | Yes |
| Colombia | NIT | Digits plus a check digit (DV) | Yes |
Individuals in the United States often use a Social Security Number (SSN) or an ITIN instead of an EIN. The validator does not process SSNs or ITINs.
Where the ID goes on a document
Invoices and many other business documents show the tax ID of the issuer and, depending on the country and the amount, of the customer too. A wrong digit can delay a payment or make the document unusable for the customer's accounting.
In the app, the company profile and each customer or supplier validate the ID when you save it, with the rules of the country. You can then issue documents such as an invoice, a quote or a purchase order.
Frequently asked questions
How do I know if an EIN is valid?
An EIN has nine digits, usually written 12-3456789. The first two digits are a prefix, and the IRS only assigns certain prefixes. The validator checks both the length and the prefix, but only the IRS can confirm that an EIN was actually issued to a business.
Can the validator tell me who owns the number?
No. It never looks anything up. It tells you whether the number is well formed. To confirm that a business exists and is active, use the tax authority's website or ask for its registration certificate.
What is the check digit?
A final digit or character calculated from the others with a fixed formula. It catches most typing mistakes, such as a swapped or wrong digit, so a number with the wrong check digit is almost surely mistyped.
Is the number I type stored anywhere?
No. The check runs in your browser and the number is neither sent to our servers nor stored.
Sources
- IRS: Employer ID numbers (EIN) (opens in a new tab)
- IRS: How EINs are assigned and valid EIN prefixes (opens in a new tab)
- SAT (Mexico): RFC (opens in a new tab)
- SUNAT (Peru): RUC (opens in a new tab)
- SII (Chile): RUT (opens in a new tab)
- SRI (Ecuador): RUC (opens in a new tab)
- DIAN (Colombia): NIT and RUT (opens in a new tab)
Text reviewed on by the editorial team. Legal values are taken from the rule in force on each date.
Documents for this calculation
- Sales invoicePDF invoice as a draft or business record of your sales. It is not an electronic sales invoice: if you are required to invoice, you must issue it electronically.
- QuotePrice proposal for products or services with validity, terms and customer acceptance.
- Purchase orderFormal order to a supplier with products, prices, payment and delivery terms.