No, travel insurance must be purchased prior to departing for your trip.  If you would like cover for trip interruption, emergency medical, and medical evacuation, consider purchasing an  International Medical Plan which may be purchased after  departure.

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• I have already departed from my primary place of residence. May I purchase cancellation insurance for a return trip home?
• Can travel insurance be purchased after I have departed for my trip?
• The resort that I will be staying at next week was just damaged by a hurricane. If I cancel my trip now, will I be reimbursed for my pre-paid non-refundable costs?
• May I purchase travel insurance for a trip if I am not returning to the United States?
• Am I required to insure the full prepaid, nonrefundable trip costs when I purchase travel insurance?