Here are my mandatories, for a group of 6:
cash/ travellers checks/credit cards
a half gallon of super good lotion, the same of #4 and #30 weight sunblock (we mix for the ones in between), and at least a quart of aloe vera.
some kind of after bite stuff, for skeeters. benadryl, ambesol, rhuligel, after bite, something like that
anti skeeter stuff, deepwoods off, 1 oz, or this year i'm also going to try the Avon skin-so-soft bug guard 4 oz
bandaids, a couple big ones
zinc oxide, just in case one lil spot gets super sunburned
chapstick with sunblock
some kind of tummy medicine, just in case. immodium/tums
small sewing kit
film/batteries/lenspaper/extra lens caps, front and back
books to read
tea bags/ coffee
ziplock bags, small and large
lightweight waterproof jacket
will have cokes, grape soda, sprite, orange in room when arrive- call ahead 3 flats for 6 people
12 gallons of water in room ahead of time
two pairs of shorts. one shirt for emergencies. rarely used.
trash bags for bringing back conch shells so they don't stink up the luggage.
You won't need a lot in San Pedro, for a few ideas on what to bring and not to bring, there are a couple detailed discussions on this on our message board at these links:
Here is a very detailed list put together by Lan Sluder of Belize First Magazine:
This is the packing list I put in my new Guide to Mainland Belize. It's really for those visiting the mainland rather than just San Pedro, but a few items may be of interest.
Belize First http://www.turq.com/belizefirst/
What to Pack and Bring
Belize is a very casual country. You don't need evening clothes or even a coat and tie or other U.S.-style business dress. You'll live in tee-shirts, shorts, loose-fitting slacks and shirts. A really dressy occasion for men might require a guayaberra or collared shirt and long pants; for women a simple skirt or dress.
Leave all your fancy jewelry and Rolex watches at home. They will impress only thieves. Also leave your rain gear at home. It probably will rain, but raincoats just make you sweat.
Here are ideas for your packing list:
Light-weight cotton clothes or quick-drying cotton/synthetic blends such as those sold by Ex Officio (tel. 800-644-7303, www.exofficio.com) and other travel stores.
Comfortable walking shoes. Consider light boots for hiking and sandals for the beach.
Extra swimsuits and tee-shirts.
Maps, guidebooks and your favorite reading material. If available in Belize, these may cost more than back home and may be out of date.
Cap or hat - be sure it's one that won't blow off in windy conditions on the water. You can't beat a Tilley Endurables hat (tel. 800-363-8737, www.tilley.com).
Sunglasses - the darker the better.
Small flashlight with extra batteries, baggies in various sizes, a roll of duct tape, a large garbage bag, pen and writing pad, and Swiss Army-style knife - with these you can go anywhere and do anything.
Your favorite snacks - many American brands are available in Belize, but they are expensive.
Extra film, camera battery or the digital equivalent - you'll shoot many more photos in Belize than you think you will. Film is readily available in Belize, but it's expensive.
Health kit consisting of your prescription medicines and a copy of your eyeglass prescription, plus aspirin, insect spray with a high percentage DEET, sunscreen (more than you think you'll need), Pepto-Bismol or other tummy medicine, bandages, sun-burn lotion, toilet tissue, moist wipes, seasick pills and other over-the-counter medicines.
Battery-operated radio if coming during tropical storm/hurricane season (June-November).
Snorkel mask - you can rent snorkel and dive gear in Belize, but rental masks often don't fit well.
Head lamp if you are going caving or river cave tubing.
Cotton sweater or light jacket may be needed in the winter, especially on the water or in the higher elevations of the Mountain Pine Ridge.
Frisbees and baseball-style caps - they make good small gifts. For gifts, some people also bring fishing lures and tee-shirts or other clothing items with U.S. sports insignia.
Click here (http://AmbergrisCaye.com/pages/town/thingstobring.html) for another very complete list for Belize prepared by a tour agency.