How to choose a liveaboard

Two trips on the same boat can be completely different. The itinerary decides which sites you can reach, and the month decides what the water is doing when you get there. Pick the destination and the season first, then look for boats that run that route in that window.

Many liveaboard regions only operate for part of the year. The Similan Islands national park closes in the wet season, Tubbataha is only reachable for a few months in spring, and Socorro trips stop during the summer hurricane season. Check the season strip for each destination before you compare prices.

• Belize Barrier ReefApril and May; February to June is generally good. September and October carry the highest hurricane risk · liveaboard or land-based
• Cocos IslandJune to November for the biggest hammerhead schools (rougher, lower visibility); December to May is calmer and clearer · liveaboard only
• FijiMay to October for clear water; November and April are shoulder months · liveaboard or land-based
• GalápagosJune to November for whale sharks and big schools (cooler, rougher); December to May is warmer and calmer · liveaboard only
• Great Barrier ReefJune to November; November to May is stinger season · liveaboard or land-based
• KomodoApril to November (dry season); December to March is wetter but good for mantas · liveaboard or land-based
• MaldivesDecember to April for visibility and calm seas; June to November for mantas, including Hanifaru Bay · liveaboard or land-based
• Northern Red SeaMarch to May and September to November · liveaboard or land-based
• PalauNovember to April (dry season); October and May are good shoulder months · liveaboard or land-based
• Raja AmpatOctober to April · liveaboard or land-based
• Rangiroa and FakaravaJune to October (drier, grouper spawning in Fakarava around the June or July full moon); December to March for hammerheads in Rangiroa · liveaboard or land-based
• Similan IslandsMid-October to mid-May (park season); peak November to April · liveaboard only
• Socorro IslandsNovember to May, liveaboard season only · liveaboard only
• Tubbataha ReefsMid-March to mid-June only; April and May are usually the calmest · liveaboard only

Boats range from a dozen guests to more than thirty. Fewer guests usually means smaller dive groups, quieter sites and more flexibility in the schedule. Ask two specific questions: how many guests on this departure, and how many divers per guide in the water.

If you are newer to diving, a smaller group with a guide close by is worth more than a bigger cabin.

Most liveaboards offer three or four dives a day, sometimes including a night dive. Look at the sample schedule and count the dives you will realistically do. The first and last days are often short, so a seven-night trip may have five or six full diving days.

• Dives per day, and whether the day starts before sunrise.
• Tender boats (RIBs or dinghies) versus diving from the main deck. Tenders let the boat drop you on a current line and pick you up wherever you surface.
• Nitrox, whether it is free or charged per fill. On a three- or four-dive day it can extend your bottom time.

Remote and current-swept routes often ask for an Advanced Open Water certification and a minimum number of logged dives. Socorro and the Galápagos commonly require both. These rules exist because the sites have strong currents, deep walls and no easy way back to shore.

Read the requirement for your exact departure and be honest about your logbook. If you are close to the line, a land-based trip to an easier destination first is the better plan. Our guide on which certification you need lists what each destination expects.

We don't rate boats for safety, and no website can tell you a boat is safe. What you can do is ask the operator directly and judge the answers.

• Is there emergency oxygen on board, and enough for a long transfer to shore?
• What is the evacuation plan from the most remote point of the route, and how long would it take?
• Is there satellite communication when out of phone range?
• Are surface marker buoys required for every diver, and does the boat provide them?
• Who leads the dives, and what are their qualifications?

Clear, specific answers are a good sign. Vague ones are worth noticing.

The advertised price rarely covers everything. Ask for the full list before you compare two boats.

• Park and port fees, often paid in cash on board.
• Nitrox and equipment rental.
• Crew tips. Many boats suggest an amount, commonly around 10% of the trip price.
• Transfers and hotel nights before and after, since you can't fly straight after diving.
• Dive accident insurance. Many liveaboards require proof of it before boarding.

Plan your flights around a surface interval. Widely used guidance from the Divers Alert Network is to wait at least 18 hours before flying after multiple dives or several days of diving. On a liveaboard, that usually means a full day on land before your flight home.

If you get seasick, ask about the crossing to the first site and the typical sea state in your month. Some routes start with an overnight open-water passage.

Finally, this guide is for planning only. Conditions change, and the boat's crew will have the final word on every dive.