When USICS approves a Certificate of Citizenship, they then issue it to you. If you are above the age of 14 then you may be expected to go to a USCIS office to engage in an Oath of Allegiance ceremony. Some individuals will have their interview and take the Oath of Allegiance on the same day. If the applicant is approved and below the age of 14 then they may not be expected to take the oath of Allegiance.

What if USCIS Denies My Certificate of Citizenship (Form N-600)? 

If you have been denied a Certificate of Citizenship then, you have 30 days from the date of their decision to file for an appeal. In order to file an appeal an individual must file Form l-290B (Notice of Appeal or Motion). If the 30 days from the decision has passed then the applicant cannot refile a Form N-600 (Certificate of Citizenship) or it will be denied. Instead, if the 30 days have passed an applicant should file a motion to reopen on the Form l-290B.