Citizenship · Form N-400

The N-400, prepared in a fraction of the time.

Five years of addresses, trips, jobs, and taxes — the N-400 is a memory test disguised as a form. Lexfill walks your client through it step by step, keeps the dates consistent, and hands you a filled application ready to review.

Form N-400, guided end to endTrips & residence kept consistent
Document checklist · Naturalization
Collected 2 of 4 — client re-uploads in one tap
Green card (both sides)approved
Travel recordsuploaded
Tax return transcriptswaiting
Marriage certificate (3-yr rule)if applies
What Lexfill prepares

Everything a naturalization case files.

Form N-400Application for Naturalization
Document checklistGreen card, travel, taxes
Guided intake5 years, one question at a time
AI reviewTrips & dates cross-checked
Built for N-400

Five years of history, collected without the dread.

Clients don't fail the N-400 on eligibility — they fail it on recall. Lexfill breaks the history into small questions, keeps a running timeline, and flags what doesn't add up.

Guided intake

Your client answers one plain question at a time.

Addresses, employment, trips abroad, marital history — one plain question at a time, with the client pausing to check a passport stamp and resuming from the same link. The eligibility basis stays attorney-side.

  • Timeline-shaped questions for the 5-year history
  • Runs in English, Spanish, Turkish, Arabic, or Chinese — RTL included
L
Lexfill intakeguiding Fatima
English
Since becoming a permanent resident, have you taken any trips outside the U.S. of 6 months or longer?
No — my longest trip was three weeks in Turkey.
Time outside the U.S. · 18 of 44
Document intelligence

Upload a document, watch the case file build itself.

The green card, travel records, tax transcripts, and — for the 3-year rule — the marriage documents land on one checklist. Lexfill identifies each upload and reads the key details into the record.

  • Card numbers and dates extracted automatically
  • Approve or reject each document; clients re-upload in one tap
  • Nothing saves to the profile until you confirm it
passport-scan.jpg
Client profile
NameTomás Herrera
BornMar 14, 1991
CountryMexico
PassportG4589
Auto-filled forms

Review-ready PDFs, filled straight from the answers.

When the intake completes, the N-400 is a filled, review-ready PDF — the five-year history landed consistently across every part, with the attorney-side sections handled in your console.

  • Residence, employment, and travel filled from the timeline
  • Eligibility basis stays attorney-side
  • Page-by-page proof of the real USCIS form
Filled from the intake
Form N-400 · ready to proof
Residence & employmentfilled
Time outside the U.S.filled
Eligibility basisattorney-set
Page-by-page proofside by side
Review flags

A second pair of eyes before it goes out the door.

Lexfill reads the whole timeline together and flags what doesn't reconcile — a trip whose return precedes its departure, residence gaps, totals that don't match — in plain English before the interview does.

  • The 5-year timeline cross-checked end to end
  • Explained in a sentence, not a score
NaturalizationAI reviewed
Continuous residence5 years, 2 months
Trips abroad4 reported
One trip's return date (May 12, 2024) is earlier than its departure date (June 2, 2024). Confirm the dates.
Selective ServiceRegistered
N-400 questions

Naturalization filing, answered.

What is Form N-400?

Form N-400, Application for Naturalization, is how a lawful permanent resident applies for U.S. citizenship — generally after 5 years as a resident, or 3 years when married to a U.S. citizen. Lexfill guides the applicant through the whole form and fills it for attorney review.

What documents does an N-400 need?

The core item is a copy of the green card (both sides). Depending on the case: travel records, IRS tax transcripts, the marriage certificate and proof of the spouse's citizenship for the 3-year rule, name-change documents, and court records if any. Lexfill's checklist covers them all.

How does Lexfill handle the 5-year history?

As a timeline, not a table. The intake asks for addresses, jobs, and trips one at a time and keeps a running record; the AI review then cross-checks it — impossible date orders, gaps, and totals — and flags issues in plain English before you review.

Does the applicant need to speak English for the intake?

The intake itself runs in English, Spanish, Turkish, Arabic, or Chinese, and answers arrive in your console in English. (The naturalization English requirement applies to the USCIS interview, not to how your client completes intake — exemptions are the attorney's call.)

Does Lexfill give legal advice?

No. Lexfill prepares the record — intake, documents, filled N-400, and flags. The attorney reviews, edits, approves, and files everything.

Can we switch to Lexfill from Clio or another practice management tool?

Yes. Lexfill integrates with Clio directly: connect your account, import your contacts and matters in a click, and push completed work back to Clio when you're done. On a different vendor? We'll do your migration for free — our team moves your clients and matters into Lexfill for you, usually within a few days.

Free for your first 3 matters

Prepare your next N-400 with less friction.

Create your firm workspace, send the naturalization intake, and review a filled N-400 with the timeline checked.

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