Both put you on a ship within the hour of landing. The difference shows up the night before you sail.
Most Caribbean and Bahamas sailings out of South Florida embark from one of two ports — Port Everglades in Fort Lauderdale, or PortMiami — and which one your ship uses matters more for your pre-cruise logistics than most people plan for.
Ten to fifteen minutes from Fort Lauderdale–Hollywood International Airport, with embarkation traffic that is generally lighter than Miami’s. If you are flying in the same morning you sail — which we would still advise against — this is the more forgiving of the two.
The busier of the two by cruise volume, which means more ships embarking on the same day and correspondingly longer terminal queues. The trade-off is Miami itself: South Beach, Wynwood and a livelier city if you are building in a night beforehand rather than treating the airport as a straight line to the ship.
Fly into whichever airport matches your ship’s actual home port — check this before booking flights, since the two are not interchangeable on cruise day. And regardless of which port, add one night in Florida before you sail. Cutting it fine on embarkation day remains the single most common way to miss a cruise entirely.