The Application for Naturalization, Form N-400, must be properly completed and signed. USCIS will not accept a stamped or typewritten name in place of a signature. All the signatures in form n 400 must be handwritten and original. You may place an “X” mark instead of a signature if you are unable to write in any language. The application MUST contain the signature of the applicant or parent or legal guardian, if applicable. USCIS will reject your Form N-400 if it is not signed.
So how exactly to sign form n 400? At the current version of Form N-400 signature is required in the following parts.
Part 13. Applicant’s Statement, Certification, and Signature
Put your handwritten original signature. If someone assisted you in completing the application, select the box indicating that you used a preparer (interpreter).
Part 14. Interpreter’s Contact Information, Certification, and Signature
If you used anyone as an interpreter to read the instructions and questions on this application to you in a language in which you are fluent, the interpreter must fill out this section. The interpreter must sign and date the application.
Part 15. Contact Information, Declaration, and Signature of the Person Preparing this Application, if Other Than the Applicant
This section must contain the signature of the person who completed your application, if other than you, the applicant. If the same individual acted as your interpreter and your preparer, that person should complete both Part 14 and Part 15. Anyone who helped you complete this application MUST sign and date the application. If the person who helped you prepare your application is an attorney or accredited representative whose representation extends beyond preparation of the application, he or she may be obliged to also submit a completed Form G-28, Notice of Entry of Appearance as Attorney or Accredited Representative, along with your application. USCIS will reject your Form N-400 if it is not signed by the preparer you used to prepare the questions on the application.
Do not complete Part 16. Signature at Interview and Part 18. Oath of Allegiance. The USCIS Officer will ask you to complete these parts later at your interview.