Fill out and sign Form N-400 online.

What is Form N-400?

Form N-400 is published by US Citizenship and Immigration Services. It is used to apply for US citizenship through naturalization.

Who needs to fill out Form N-400?

Lawful permanent residents who meet the residency, physical presence, and other eligibility requirements for naturalization.

How to fill out and sign Form N-400 online

1. Click Fill Form N-400 online above. Pdfmark fetches the official PDF from US Citizenship and Immigration Services and opens it in the in-browser editor.
2. Click any field on the form to add text. The form is filled out by the applicant, so add their details where the form asks for them.
3. Add your signature by drawing it, typing it, or uploading a PNG. Form N-400 is signed by the applicant.
4. When the form looks right, click Download. Pay $2.99 through Stripe Checkout, and the finished PDF downloads straight to your computer.

The whole flow usually takes two or three minutes. There's no account, no subscription, and no per-page fees.

How much does it cost?

Pdfmark charges a flat $2.99 in US dollars per finished form, paid through Stripe Checkout when you download. Editing is free for as long as you need it. If you don't download, you don't pay.

Is it safe to fill out Form N-400 on Pdfmark?

Yes. Your filled-in PDF is stored in encrypted Vercel Blob storage with an unguessable random identifier, and the session auto-deletes 24 hours after upload. Pdfmark never inspects, copies, or analyses the contents of your form. See the privacy policy for the full details.

Where does the official form come from?

The PDF Pdfmark loads is the canonical Form N-400 published by US Citizenship and Immigration Services. We fetch it directly from the source ( https://www.uscis.gov/sites/default/files/document/forms/n-400.pdf) and load it into your editing session. Pdfmark is not affiliated with or endorsed by US Citizenship and Immigration Services.