Before Thailand.
Your practical checklist.

Use Thai e-Visa and the Thai embassy responsible for your application to check your nationality, travel document, purpose and intended stay. Check passport validity, required supporting documents and any visa application before buying non-refundable arrangements that depend on them. A tourism exemption for one passport or purpose does not establish permission for another.

The official TDAC FAQ currently allows submission up to 72 hours before entry. Have your passport, arrival flight or transport details, Thai accommodation address, email and any requested health information ready. Use the Immigration Bureau's official service, save the returned record and follow its instructions if your details change. TDAC is an arrival card, not a visa; airside transit without passing immigration has different requirements.

Compare the policy with the activities you are actually planning: a dive course on Koh Tao, trekking near Chiang Mai, a boat trip or any vehicle hire. Check medical and evacuation cover, existing conditions, activity exclusions, claim limits and the insurer's emergency number. Save the policy and contact details somewhere accessible to you and a travel companion.

Discuss vaccination and personal health needs with a qualified travel-health professional using your route and travel history. For medication, check the active ingredient and amount with the Thai FDA traveller service. Its rules distinguish controlled substances and quantities, and some require an advance permit. Keep the appropriate prescription or clinician's letter and original labelled packaging; a home prescription alone does not establish Thai import permission.

Ask your bank or card issuer about overseas use, withdrawal limits, cash-advance treatment and foreign-currency charges. Take a second usable payment method and keep it separately from the first. Have access to baht for small purchases and local transport, and read an ATM or exchange quote before accepting it; this guide does not assume a universal fee or best rate.

Save your bank's card-blocking contact and confirm that account recovery will work while abroad. If a one-time code goes to your home number, plan how you will receive it after changing the phone's data SIM. In a shared trip, record whether a hotel or transfer amount is the group total or each traveller's share; keep full card details and PINs out of shared notes.

For the first hotel, confirm the check-in date in Thailand, late-arrival process and exact address. Check the arrival airport code: Bangkok's BKK and DMK are different airports. Compare the official airport transport options with a property-arranged pickup, including luggage and the journey from a rail station or drop-off to the door.

For each onward leg, save the provider, date, departure point, destination, check-in instructions and baggage allowance. Use SRT D-Ticket for rail, the airline's own booking record for flights and the ferry operator's dated search for islands. Check whether a ticket includes the hotel or airport transfer. Before leaving, reopen the confirmations and ensure the dates match the hotel nights; a saved Diary plan is not a reservation.

Before an outdoor day, check the Thai Meteorological Department and the relevant park or boat operator. For northern sightseeing, Air4Thai provides official monitoring. Follow current beach flags and staff instructions, and ask whether a trail, cave or boat stop is open for the trip you are buying. The same destination can need a different plan on different days.

Pack temple clothing that meets the sites you intend to visit: the Grand Palace has its own detailed dress rules. Check the baggage allowance on each domestic flight before choosing luggage. If you plan to drive or ride, establish the licence requirements for your nationality and vehicle category and the insurance conditions before hiring; a rental shop's willingness to hand over a vehicle is not the check.