Dont the instructions say you cant do it online?
REQUEST FOR FEE WAIVER FOR FORM N-400
Fees are associated with filing Form N-400, Application for Naturalization, with limited exceptions.
Form G-1055, Fee Schedule, lists all current fees and fee exemptions for Form N-400. If a fee exemption for
Form N-400 applies to you, you do not need to request a fee waiver or pay the filing fee.
Fee waivers are available for those who meet specific criteria that clearly demonstrate that they are
unable to pay the fees. If you do not qualify for a fee waiver, you may qualify for a reduced filing fee. A
reduced feeis not the same as a fee waiver. For additional information, see the Instructions for Form
N-400. You may request a fee waiver by filing Form I-912, Request for Fee Waiver, or by submitting a
written request for a fee waiver, along with your paper Form N-400. If you are requesting a fee waiver,
you cannot submit your Form N-400 online and you must file paper versions of your fee waiver
request together with your Form N-400. If you are requesting a fee waiver, do not submit a payment.