Many people inquire about combining our all-inclusive island package with a short stay at Caye Caulker on their own. This is easy, but you wouldn’t go from one directly to the other. In a nutshell, all roads in Belize lead to Belize City.
No one would travel from Glovers Reef to Caye Caulker, or visa versa unless you chartered a boat, and that would be expensive (my best guess: about $1200-1500 US). You would return to Belize City from one to catch transport to the other.
We have a private boat that goes between Belize City and our island 2x a week, and the price for this transfer is included in all of our island packages. Caye Caulker is well out of the way, and we would run out of gas if we wanted to ‘swing by’ Caye Caulker on the way. (Not to mention that all of the other guests not going to Caye Caulker would not appreciate the extra hour in the boat).
Fri: fly into Belize City, take a taxi to the Biltmore and check in. Your guide will then meet you at the Biltmore at 5:30 pm. Dinner and overnight included in package. Sat: After (included) breakfast, walk to our dock 1 block from hotel (luggage is driven). Get on boat no later than 8:30 am, probably more like 8 am. Out to island by about 11-11:30 am. Tour of island, lunch. After lunch sport activities start. Sun: Island activities all day. Mon: Island activities all day. Tue: Island activities all day. Wed: Island activities all morning. Lunch on island. Boat leaves after lunch and gets back to Belize City by about 3 pm. Take a cab to either the municipal airport or the water taxi terminal to catch next transport to Caye Caulker. It’s a 20 minute flight and 45 minute boat ride. (Last water taxi AND last flight from Belize City leaves at 5:30 pm.) Dinner and overnight at Caye Caulker. (One note: after the long boat ride from the island, you would probably rather fly.) Or you can overnight at the Biltmore again (not included in half week package) and take the water taxi or flight first thing in the morning.
One final thing, you might be thinking of Ambergris Caye instead of Caye Caulker. These two islands are near each other and both have flights and water taxis, so everything here pertains to Ambergris Caye as well.