For domestic flights, it is generally recommended to arrive at the airport about 1.5 to 2 hours before departure. This time frame allows for check-in, security screening, and reaching your gate calmly. If you have already checked in online and are traveling only with hand luggage, arriving about 1 hour before your flight may be sufficient, assuming no long lines or delays. Airlines often advise being at the airport at least 2 hours before departure for domestic flights to be safe, especially in busy or large airports.