The Short Answer

Arrive 2 hours early for domestic flights and 3 hours early for international departures at SJU. The airport is busy, security lines can build during morning peaks, and the terminal layout requires more walking than a smaller regional airport.

Domestic Departures

For flights to the U.S. mainland -- New York, Miami, Boston, Atlanta, and other domestic destinations -- two hours is the standard recommendation. During peak morning departure windows (roughly 5 AM to 9 AM), security lines at SJU can be substantial. TSA PreCheck and CLEAR significantly reduce wait times. If you have either program, 90 minutes is generally comfortable for domestic departures outside the early morning rush.

International Departures

For flights to non-U.S. destinations -- Copa to Panama, Iberia to Madrid, Caribbean island flights operated as international routes -- arrive three hours before departure. International check-in requires additional documentation verification, and the international departure area at SJU has its own processing steps.

Inter-Island Flights (Cape Air / Silver Airways)

Cape Air and Silver Airways operate from the regional terminal at SJU -- a different building from the mainline terminals. Allow extra time to get there. Check-in for Cape Air closes 30 minutes before departure with no exceptions. Arrive at the regional terminal at least 60 minutes before your inter-island flight.

Peak Congestion Windows

TSA PreCheck and CLEAR at SJU

Both TSA PreCheck and CLEAR operate at SJU and are worth having for frequent SJU travelers. PreCheck lanes are consistently faster than standard lanes, especially during morning peaks. CLEAR biometric verification bypasses the ID check queue entirely. If you have both, the combination makes early morning departures from SJU nearly stress-free.

Parking and Getting to the Terminal

If driving to SJU, factor in parking time. The rental car center shuttle adds 15-20 minutes for drop-off. Long-term parking lots at SJU can fill during peak periods. Budget extra time if driving versus Uber or Lyft, which can drop you at the terminal curb.