The purpose of Form N-644 is for an alien or non-citizen national of the United States who dies as a result of injury or disease incurred by active duty with the United States Armed Forces during specific periods of hostilities may be granted citizenship posthumously.

To qualify for posthumous citizenship with Form N-644, the veteran must have been an alien or non-citizen national of the United States who served honorably in active duty status.

If the Form N-644 is approved, the decedent will be granted a Certificate of Citizenship in his or her name. The Form N-644 certificate establishes that the decedent is considered a citizen of the United States as of the date of his or her death. The posthumous certificate of citizenship granted under a Form N-644 application is an honorary status commemorating the bravery and sacrifices of the veteran. The Form N-644 application must be filed no later than two years after the death of the veteran.

Form N-644 requires that only the following may file:

1. Spouse
2. Father or Mother
3. Son or Daughter
4. Brother or Sister

The decedent's representative, either executor or administrator of his or her estate may file Form N-644. A guardian, conservator, or a committee of decedent's next of kin may also file File N-644.