Diving trip
A trip built around diving: health check, certification or a course, insurance that actually covers diving, and gear — own or rental. The list adapts to your level.

[ ] Fill out the diver medical questionnaire early
    Every dive center uses the standard RSTC form. Some answers (asthma, ear or heart issues) require a doctor's clearance letter — find out before you fly, not on dive day.
[ ] Confirm your insurance actually covers diving
    Standard travel insurance often excludes diving past a certain depth, or diving altogether. A diving-specific policy (like DAN) covers evacuation and a decompression chamber, which regular plans usually don't.
[ ] Book the course in advance
    Good instructors book out weeks ahead in season. Check the prerequisites: a 200m swim test and treading water for 10 minutes is a common entry requirement.
[ ] Bring photos and ID for the certification card
    You'll usually need 1–2 passport-style photos — some centers print the certification card on-site but still ask you to bring your own.
[ ] Bring your certification card and logbook
    Many dive sites and wrecks require a proven dive count or level (Advanced) — without the card and logbook, the best spots simply aren't open to you.
[ ] Consider a Nitrox certification
    If you don't have it yet — it's a couple of hours of theory and meaningfully extends no-decompression time on multi-day dive trips.
[ ] Book the dive center or liveaboard
    Check reviews and whether O2 and a first-aid kit are on board, not just the price. Liveaboard spots sell out months ahead in season.
[ ] Plan your flight home around the no-fly rule
    You need at least 12–24 hours on the surface before flying after diving, or you risk decompression sickness. Factor this into your return flight booking.
[ ] Practice ear equalization beforehand
    If ears have given you trouble before on flights or dives, practice the technique at home and pack a nasal spray — it clears congestion before the first descent.
[ ] Pack motion sickness remedy
    Boat rides in a swell get to even experienced divers. Pack a remedy category in advance — taking it once you're already on deck is often too late.
[ ] Reserve rental gear sizes ahead of time
    Fins and a wetsuit in your size and thickness (for cold water) go fast in peak season — message the center weeks ahead, don't count on picking it up on arrival.
[ ] Get your regulator and BCD serviced
    Annual regulator service isn't a formality: a malfunction underwater is more dangerous than anywhere else. Do it weeks before the trip, not the night before.
[ ] Check the airline's rule on dive tanks
    A tank can only fly empty with the valve open — a pressurized or closed-valve tank simply won't be accepted.
[ ] Pack a save-a-dive kit
    Spare o-rings, a mouthpiece, a mask strap, string and tape — a small gear failure shouldn't cost you a whole day of diving far from a dive shop.
[ ] Charge or replace the dive computer battery
    Bring a spare battery of the right type if your computer isn't rechargeable — most dive islands won't have the exact one in a shop.
[ ] Pack reef-safe sunscreen
    Some marine parks (Hawaii, Palau) ban regular oxybenzone sunscreens outright — check the local rule ahead of time and buy a reef-safe one before you go.
[ ] Bring cash for marine park fees
    Many marine national parks charge a separate entry fee in cash on-site, card often not accepted. Small bills help.
[ ] Pack a rash guard
    Protects from sun on the surface and light jellyfish stings — worth packing even if a swimsuit alone would be warm enough.
[ ] Leave your dive plan with someone on land
    Even with a guide: someone outside the group should know when you went under and when to expect you back.
[ ] Plan a no-dive buffer day before flying
    Beyond the 12–24 hour minimum, a spare day covers you if the last dive gets cancelled or pushed by weather.

Checklist from Unload: https://unloads.me/c/diving-trip