Importing Contacts

Does the sequence of the Contact ID numbers change if I delete a Contact that I’ve imported?

Contact IDs are internally generated identifiers that can be customized in your account settings.

As you add Contacts to your account, the associated IDs are tracked in sequential order. When you import a CSV file of records, the same rules apply to their IDs as if they were manually created. If you delete a Contact that has been imported, the next Contact you add to the account, whether manually or via import, will inherit the next ID number in the sequence.


  • Contact A was created and has been assigned the ID of #1234.
  • Contact B was added to the account after Contact A and, as a result, has been assigned the ID of #1235.
  • Contact A has since been deleted.
  • Contact C was then added as a new record (either manually or by import) and has an ID of #1236, because of the sequential order the ID numbers follow. Contact C will never be assigned ID #1234 since it still belongs to Contact A, even though Contact A has been deleted.

Learn more about Contact ID numbers here.