Montserrat Immigration Fairness Act - Requires the Secretary of Homeland Security (Secretary) to grant lawful permanent resident status to certain nationals of Montserrat previously granted temporary protected status in the United States (and specified family members).

Authorizes aliens previously ordered excluded, deported, or removed, or ordered to depart voluntarily, to apply for adjustment of status under this Act.

Requires the Secretary to provide work authorization and related documentation to principal aliens seeking the benefits of this Act.

Directs the Secretary to provide specified administrative review procedures for such aliens and their qualifying family members.

States that the granting of adjustment of status for principal aliens under this Act shall not reduce the number of available immigrant visas.