Do I need to repeat domain validation (DV) for subdomains?

So, you’ve gotten an SSL/TLS certificate and validated your base domain, but now you need certificates to cover additional subdomains. Can you re-use your previous validation, or do you need to repeat the process?

  • If you have validated, you do not need to go through domain validation for a new CSR for (or any other subdomain of unless the original validation has expired. (Note: DV is valid for 825 days between validations.)
  • If you are adding to the CSR of a previously-issued certificate covering (for example, when reprocessing a multi-domain certificate), you do not need to go through domain validation for unless the original validation has expired.
  • However, in both of the above cases, if your initial validation was for, you do need to go through domain validation for or (but not for
Note: If you add a new domain name when reprocessing a multi-domain certificate and wish to use the CNAME or file lookup validation method, you will need to create a new CNAME or file for validation. These DV methods both require a unique value that is incorporated into the CNAME or file.
Thank you for choosing! If you have any questions, please contact us by email at, call 1-877-SSL-SECURE, or just click the chat link at the bottom right of this page. You can also find answers to many common support questions in our knowledgebase.

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