Código de Identificación Fiscal Checker – A Complete Guide to Validating Spanish CIF Numbers

What Is a CIF Number?

The CIF (Código de Identificación Fiscal) is the corporate tax identification number assigned by the Spanish Tax Agency to legal entities registered in Spain – companies, partnerships, foundations, etc. It is essential for filing taxes, issuing invoices, and customs clearance. The CIF consists of 9 characters: a leading letter (indicating the entity type) + 7 digits + a check digit (number or letter). For instance, a limited liability company uses B12345678, while a public corporation uses A12345674.

It is worth noting that since 2010 the CIF has been officially replaced by the corporate NIF (Número de Identificación Fiscal). However, in everyday commercial and trade practice – especially on invoices and customs documents – the term "CIF" is still widely used. So whenever you see "please enter your CIF", you can safely fill in your corporate NIF. [reference:0][reference:1]

How to Use This Código de Identificación Fiscal Checker

Three simple steps to verify whether your CIF number is correctly formed:

1. Paste or type the 9‑character CIF code into the input field (the tool automatically strips symbols and converts to uppercase).
2. Click the "Validate" button.
3. Read the result – the checker will tell you if the format is valid and if the check digit matches.

You can try the example numbers to see how the tool works. If you enter an invalid code (wrong length, invalid leading letter, or incorrect check digit), you will receive a clear error message.

This Código de Identificación Fiscal checker is completely free, no registration required – ideal for cross‑border sellers, Spanish business owners, and accounting professionals.

Frequently Asked Questions

1. Does this CIF checker confirm that the company actually exists?

This tool validates the syntactic correctness and the modulo‑23 checksum of the CIF. A "valid" result means the number is structurally sound. To check whether the company is actively registered, you must consult official Spanish registers, such as the AEAT VAT verification service or the EU VIES system. [reference:2]

2. What’s the difference between CIF and NIF?

CIF was the old corporate tax identifier used before 2010. NIF is the current unified taxpayer identification number for both individuals and legal entities in Spain. For corporations, the corporate NIF uses exactly the same structure as the old CIF – the only change is the name. Many people still say "CIF number", but the official tax ID for companies is now the NIF. [reference:3]

3. How does CIF differ from NIE?

NIE (Número de Identificación de Extranjero) is a combined identity and tax number issued to foreign nationals residing in Spain. It is used for personal tax registration, opening bank accounts, etc. The NIE format starts with X, Y, or Z, followed by 7 digits and a check letter (e.g., X1234567L). CIF is for legal entities; NIE is for foreign individuals – they are not interchangeable. [reference:4]

4. Why does my CIF come back as invalid?

Common reasons: the length is not exactly 9 characters; the first letter is not allowed (valid letters: A, B, C, D, E, F, G, H, J, N, P, Q, R, S, U, V, W); the input contains invalid characters; or the modulo‑23 check digit does not match the computed value. Double‑check your entry, or test with one of the provided examples to ensure the tool is working correctly. [reference:5]

5. Can I validate multiple CIFs in batch?

This page is designed for single checks. For bulk validation, you can integrate our API endpoint at /iso-checker with parameters type=cif&number=your_number. Feel free to contact us for more details.

6. Is this service really free?

Absolutely – no payment required. OkeyTool is committed to providing handy online utilities for everyday use.

If you have further questions or encounter any issues with this Código de Identificación Fiscal checker, please reach out via the contact info at the bottom of the page. Thank you for using our tool!