How to check an already issued tax certificate
You can verify a tax certificate from the "Document comparison using secure verification code" service that you will find in the highlighted block "Notifications and document comparison".
All certifications issued, regardless of how they were requested, will have a verification code so that the recipient can verify their authenticity and validity.
It is not possible to use this option until the certification has been issued.
This comparison is useful if the certification has been received by regular mail or email or another means other than our website.