Some regions, like the Schengen Area , generally require only three months of validity beyond your planned departure date. Permanent Residency (Immigration)
Six-Month Validity Update - U.S. Customs and Border Protection 6 Month Rule
For U.S. Lawful Permanent Residents (Green Card holders), the "6 month rule" refers to travel outside the United States. Some regions, like the Schengen Area , generally