Packing for a warm place: the twenty things that matter

I have packed for a hundred warm trips and the list keeps getting shorter. What follows is the core of it, the things that earn their place in every bag whether the destination is a Spanish beach or a Polynesian lagoon. The packing list builder turns it into a checklist for your trip type and length, and remembers what you have ticked.

Sun

• Reef-safe sunscreen, SPF 50. Mineral formulas are required by law in Hawaii, Palau and parts of the Caribbean and are kinder to every reef you swim over. Buy it before you fly; resort shops charge three times the price.
• A hat with a brim that stays on. Trade wind coasts like Aruba and Zanzibar eat floppy hats. A chin strap is not glamorous and neither is sunstroke.
• Sunglasses with real UV protection and a rash vest or long-sleeved swim shirt for snorkelling. The back of your neck at four degrees south does not care what the sunscreen promised.

Water

• Water shoes for pebble beaches (the Riviera), coral (the Maldives) and rock pools (Rottnest).
• A dry bag for boat days: phone, cash, passport copy.
• Your own snorkel mask if you will use one more than twice. Rental masks leak.

Clothes

• Linen and thin cotton, light colours, loose. Two swimsuits so one is always dry.
• One warm layer. Every warm place has cold moments: the plane, the desert at night, a rooftop bar in Dubai in January, the Haleakalā summit.
• A sarong or light scarf: beach towel, temple cover, shade, picnic blanket.
• Sandals you can walk in for a day and one pair of closed shoes for hikes, scooters and gecko-proof evenings.

Health and paperwork

• Insect repellent with DEET or picaridin where dengue exists, and an after-sun with aloe.
• Rehydration sachets, plasters, your usual medicines in original packs, and travel insurance details saved offline.
• Passport copies, a universal adapter, a power bank for the places with power cuts, and a local SIM plan researched before landing.

Leave at home

Hair dryers (hotels have them), more than two pairs of shoes, jeans in the tropics, a full-size towel, and the idea that you will read four books. You will read one, on a hammock, slowly.