Aircraft buyer guide
FAA N-number format: digits, letters and common input errors
An FAA N-number begins with N and has up to five following characters. The permitted patterns use digits first, optionally followed by one or two letters. Checking the format does not establish that a mark is assigned, registered or available.
By Aerovidence · Reviewed
The three FAA format patterns
The FAA describes three digit-and-letter arrangements. The strings below illustrate formatting only; they are not aircraft records, availability results or recommended searches.
| Pattern | Formatting illustration |
|---|---|
| One to five digits after N | N12345 |
| One to four digits, then one letter | N1234Z |
| One to three digits, then two letters | N123AZ |
Official references: FAA forming an N-number. Sources checked .
Check zeroes, letters and punctuation
The first digit cannot be zero. The letters I and O are not used in the alphabetical suffix. A digit cannot follow the suffix letters. Copy the complete mark carefully from a document; do not replace an uncertain I or O with a digit and silently treat the guess as an aircraft identity.
- Keep the N prefix when recording the mark.
- Check a photograph or original document if a character is ambiguous.
- Remove surrounding whitespace when copying into a search box.
- Treat a spelling correction as a new search, then compare the returned identity fields.
Official references: FAA forming an N-number. Sources checked .
A valid pattern is not a valid aircraft record
A mark can fit a format without identifying the aircraft you intend to research. Assignment, reservation, registration status and historical use are different questions. Check the actual official entry and its dates; a successful format check is not evidence of airworthiness or ownership.
Official references: FAA N-Numbers · FAA registry field definitions. Sources checked .
Choose the next search
Use the free N-number lookup when the mark is readable. If you only have a manufacturer serial number, use the separate official Serial Number Inquiry and verify the manufacturer and model. A missing registration result needs a coverage and identity check, not a clean-history conclusion.
Official references: FAA Serial Number Inquiry. Sources checked .
Check the public records first
How Aerovidence handles evidence · Sources and coverage limits
Continue your research
FAA N-number lookup: how to search aircraft registration
Search an FAA N-number or tail number for free. Learn what registration results mean, check the aircraft serial number and resolve missing or changed records.
N-number lookup returned no results: what to check next
Troubleshoot a missing aircraft registration result using the input format, dated source coverage, FAA inquiry, serial number and documented N-number changes.
Aircraft serial number lookup: find and verify an FAA registration
Use the FAA aircraft Serial Number Inquiry when a tail number is missing or changed, then compare manufacturer, model, serial and dated registration evidence.