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Add tax information (CSD)

Upload your Digital Seal Certificate to enable automated stamping of CFDI 4.0 invoices.

This article applies to accounts with Country of operation = Mexico. The CSD and CFDI 4.0 are a Mexico-only requirement. If your business operates in another country, your Settings › Invoicing › Tax details screen doesn’t show the CSD: you capture your local invoicing identity there instead (legal name, your local tax ID — NIF/CIF, EIN/Tax ID, depending on your country — and address), and Cord issues your invoice with a number, an immutable copy, and a PDF. In Spain, a chained Verifactu record (in beta) is created from Starter, with the company’s electronic certificate uploaded; without it, the invoice is issued as a pro forma, without registration with the Spanish tax authority.

What is a CSD and why do you need it?

The Digital Seal Certificate (CSD) is an electronic document issued by the SAT that allows you to digitally sign (stamp) your electronic invoices. Unlike the FIEL (e.firma), the CSD is used exclusively for issuing tax receipts.

For Cord to convert your approved quotes or orders directly into an official invoice with the SAT without having to re-enter data on another portal, it is mandatory to upload your CSD. CFDI issuance requires the Starter plan or above; see tax invoice allowances in Your subscription.

Before you start

  • Starter plan or above. The CSD can’t be uploaded on Free.
  • Settings permission in your organization role.
  • Complete tax details: RFC, legal name, tax regime, and issuing postal code, entered on the same screen. Without them Cord rejects the upload and asks you to complete them first.
  • Recent sign-in: because this is a sensitive action, Cord may ask you to confirm your identity again before accepting the files.

Steps to upload your CSD in Cord

  1. Go to Settings › Invoicing › Tax details.
  2. In the Digital Seal Certificate (CSD) section, choose your files and enter the password:
    • .cer file: The public certificate.
    • .key file: Your private key.
    • Key password: The password you chose when processing your CSD with the SAT (Note: this is usually different from your FIEL password). It is only used to decrypt your .key and is not stored in Cord.
  3. Click Upload CSD and connect.

Warning: the file and password travel over HTTPS/TLS to the server and fiscal provider. Cord keeps only the secret reference required to operate the integration encrypted at rest; do not describe this as end-to-end encryption. We never use your FIEL: upload only the CSD and never your FIEL (e.firma) for invoicing.

Validations and Common Errors

When you upload your CSD, the fiscal provider Cord stamps with reviews the certificate. If it is rejected, you’ll see the reason on screen. The most common cases:

  • Validity: an expired CSD (they last 4 years) is rejected; renew it on the SAT portal and upload it again.
  • RFC: Cord stamps under the certificate’s RFC, so the CSD must belong to the RFC you entered in your tax details.
  • Incorrect password: if the password can’t open the .key file, the upload is rejected.

Once accepted, the section shows CSD uploaded, and any closed quote will be able to issue its CFDI 4.0 with a single click.