Strong availability to Mexico's Caribbean and Pacific coasts, including winter and spring break for many schools. Availability for some routes pushes all the way into August 2023 if you're really planning ahead.
Fare details: No full-size carry-on bags with JetBlue or United. Upgrade for $40 each way. Checked bag: $30-$35 each way. For baggage-inclusive options be sure to compare prices on the Southwest website for your dates.