Southeast AsiaBangkokThailand eSIM and Travel Guide: Stay Connected From Bangkok to the Islands
Thailand has near-universal 4G coverage in cities and on the tourist trail, with fast 5G rolling out across Bangkok, Chiang Mai and Phuket. The easiest way to stay connected is a Roamix Thailand eSIM, which activates on arrival, skips airport SIM queues and works everywhere from the Grand Palace to remote northern guesthouses. Budget 8 to 12 GB for a two-week trip and always have offline maps ready for island driving.
Key Takeaways
- AIS leads for coverage outside the cities and on the islands, making it the best choice for island hopping and northern trekking.
- A Roamix eSIM activates automatically on arrival so you skip the busy airport SIM counters entirely.
- Cash is still essential at markets and temples, but a connected phone wallet works in most malls and restaurants.
- Most Western and Asian passport holders enter visa free for 60 days, with a Digital Arrival Card now required before landing.
- Budget 8 to 12 GB for two weeks, more if you stream or use a lot of maps across multiple islands.
Quick Facts
Thailand Connectivity
Get a Roamix Thailand eSIM and land with data ready before you hit the taxi queue.
How to Stay Connected in Thailand
Thailand has wifi in virtually every cafe, guesthouse and hotel, but speeds vary widely and public networks are not secure for banking or sensitive work. Free wifi is a supplement, not a substitute for mobile data.
Option
Best For
Notes
RecommendedRoamix eSIM
Most travellers
Instant activation, local network speeds from the moment you land, no physical SIM swap and no roaming bill.
Local physical SIM
Long stays or those needing a Thai number
Available at airport counters and convenience stores. Requires a passport and SIM swap, which leaves your home number offline.
Pocket wifi
Groups sharing one device
Another device to charge daily, with pickup, return and deposit to manage.
Carrier roaming
Very short trips with no setup time
By far the most expensive option, typically charged per day or per megabyte.
For most Thailand visitors, a Roamix eSIM is the simplest and most cost-effective way to stay connected, combining local network speed with zero setup hassle at the airport.
Get connected the moment you land in Thailand.
Get your Thailand eSIMMobile Networks in Thailand
Thailand has fast, reliable mobile networks in every city and along the main tourist corridors. AIS and True Move H (which merged with DTAC) dominate the market and both offer strong 4G coverage across Bangkok, Chiang Mai, Phuket and the Gulf Islands. A Roamix Thailand eSIM connects to the strongest available local network the moment you land at Suvarnabhumi or Don Mueang, so navigation, rideshare and messaging apps are live before you reach the exit.
The widest geographic reach in the country, strongest on the islands, in northern mountain areas and outside major cities. Leads on 5G download speed and consistent quality.
Formed by the True and DTAC merger, now the largest by subscribers with 93% nationwide 5G population coverage and dominant performance in Bangkok and major tourist cities.
Now operating under the True Corporation umbrella following the merger, sharing infrastructure with True Move H across all 77 provinces.
Typical Speeds
Expect 30 to 80 Mbps on 4G and up to 200 Mbps on urban 5G in Bangkok.
5G Status
5G is commercial in Bangkok, Chiang Mai and Phuket, with AIS leading on speed and True Move H on 5G population coverage reaching 93% nationally.
If your trip includes island hopping in the southern gulf or Andaman coasts, choose a Roamix plan that rides the AIS footprint, which maintains the most reliable signal on Ko Samui, Ko Tao and the Krabi islands.
Deep jungle treks, remote northern hill tribe villages and some smaller islands have patchy or no coverage on any network. Download offline maps of national parks before you set off.
Thai networks use widely supported LTE and 5G bands, so a Roamix eSIM works on virtually any recent unlocked smartphone without band compatibility issues.
Data Usage Guide
Thailand trips rely on maps, rideshare, restaurant reviews and a lot of photo sharing. The data needs are moderate compared to more complex transit systems, but island hopping and offline map downloads add up.
Download offline Google Maps packs for each island or trekking region over wifi before you leave your hotel, which saves data and keeps you navigating even on ferry crossings with no signal.
Data by Activity
Light Use
3 to 5 GB
Long weekend in Bangkok
Maps, Grab, food apps and social sharing across a city with fast and reliable 4G.
Standard
8 to 12 GB
Two-week tour covering Bangkok, Chiang Mai and islands
Heavy navigation between regions, ferry and flight bookings on the move and regular photo uploads.
Heavy Use
20 GB or more
Digital nomad or remote worker
Video calls, laptop tethering and cloud uploads alongside daily exploration.
Apps & Internet Freedom
Thailand has an open internet with no systematic blocking of social media, messaging or VoIP apps. Every mainstream app works normally on a Roamix Thailand eSIM.
There is no general censorship of messaging or social platforms for tourists. Some politically sensitive websites may be filtered, but this does not affect travel apps. No VPN is needed for everyday use.
Fully available for messaging and calls throughout Thailand.
FaceTime
Works normally on data and wifi with no restrictions.
Google Maps and Search
Unrestricted and essential for navigation.
LINE
LINE is the dominant messaging app in Thailand and works perfectly on a Roamix eSIM.
How to Set Up a Thailand eSIM
A Roamix Thailand eSIM is best installed over wifi at home before you fly. It activates automatically when your phone connects to an AIS or True Move H tower on landing, so you are navigating and messaging before you clear customs.
Works on eSIM capable phones including iPhone XS and newer, Google Pixel 3 and newer, and recent Samsung Galaxy models. Your phone must be carrier unlocked.
- 1
Buy your plan on the Roamix Thailand eSIM page before departure.
- 2
Install the eSIM by scanning the QR code or tapping to install over wifi.
- 3
Label it Roamix and keep your home SIM as primary for calls and SMS.
- 4
Enable data roaming on the Roamix line only.
- 5
Land in Thailand and the eSIM connects automatically, no SIM counter required.
APN Note
Roamix configures the APN automatically on most devices. If data does not start, apply the APN from your activation email and toggle airplane mode off and on.
Troubleshooting
If no data on arrival, check that data roaming is enabled for the Roamix line, try selecting the network manually, and restart the device.
Get connected the moment you land in Thailand.
Get your Thailand eSIMArrival Checklist
Complete the Thailand Digital Arrival Card (TDAC) online before your flight, as it is mandatory from May 2025.
Confirm your Roamix eSIM has connected to a local network before leaving the arrivals hall.
Download the Grab app before landing to book your taxi or rideshare from the airport without needing to queue at the official taxi desk.
Withdraw a small amount of Thai baht at an airport ATM as cash is still needed at markets, temples and smaller restaurants.
Cache offline maps of your first destination, especially if you are heading straight to an island or national park.
How locals communicate
LINE is the dominant messaging and calling app in Thailand, used by almost everyone. WhatsApp covers most international contacts.
Install LINE before arrival if you plan to book local tours, restaurants or activities, as many Thai businesses communicate primarily through it.
Airports in Thailand
Suvarnabhumi International Airport
Bangkok
Free AOT WiFi throughout the terminal. Reasonably fast but can be congested in the international arrivals hall.
Suvarnabhumi is Thailand's main international hub. With Roamix already active, you can book your Grab taxi or airport rail link ticket before clearing customs and navigate to your hotel on Sukhumvit or in the old city with no queue, no kiosk, no hassle.
Don Mueang International Airport
Bangkok
Free WiFi available. Smaller than Suvarnabhumi and primarily serves budget carriers including AirAsia and Nok Air.
Don Mueang is farther from central Bangkok than Suvarnabhumi and taxis can be expensive without Grab. A Roamix eSIM means Grab is bookable the moment you land, saving you from metered taxi negotiations.
Phuket International Airport
Phuket
Free WiFi in the international terminal. Coverage is good in the arrivals hall.
Phuket taxi and shuttle prices from the airport are notoriously negotiated rather than metered. Having Roamix data active means Grab comparison pricing and Patong Beach hotel confirmation are both in hand before you leave the terminal.
Chiang Mai International Airport
Chiang Mai
Free WiFi available. Small, efficient airport with quick arrivals processing.
Chiang Mai's airport is 10 minutes from the old city moat. Roamix data lets you book your first night's hotel or a pickup from your guesthouse in real time if plans changed en route.
Visa & Entry for Thailand
Thailand grants 60-day visa-free stays to nationals of 93 countries including most of Europe, the US, UK, Canada, Australia and much of Asia. From 2025 a Digital Arrival Card must be completed online before arrival, replacing the old paper form.
eVisa / ETA
Nationals of 31 countries can obtain a 15-day visa on arrival for a fee of 2,000 THB. Thailand also operates an e-Visa system for advance applications. Visa-free travellers do not need a pre-arranged document but must complete the Thailand Digital Arrival Card online up to 3 days before arrival.
Passport validity
Your passport should be valid for at least 6 months beyond your intended departure date.
Onward ticket
Proof of onward or return travel is required at immigration and may be checked by your airline at check-in.
Complete the TDAC before flying using your home wifi, and keep the confirmation accessible on your Roamix eSIM-connected phone at the immigration desk.
Entry requirements change. Confirm current rules with the Royal Thai Embassy or official Thai immigration sources before booking.
Get connected the moment you land in Thailand.
Get your Thailand eSIMMoney & Payments in Thailand
The Thai baht is cash-forward. Markets, street food stalls, temples and many smaller restaurants are cash only. Keep some baht on you at all times.
Cash vs Card
Cards are accepted at malls, mid-range restaurants and larger hotels. Outside tourist-heavy areas and for small purchases, cash is king.
ATMs
ATMs are widely available but typically charge a 220 THB foreign transaction fee per withdrawal. Choose to be charged in THB rather than your home currency to avoid poor dynamic conversion rates.
Payment Apps
PromptPay is the dominant local payment system. Apple Pay and Google Pay work in international-facing venues. A connected Roamix eSIM keeps your banking app working to track spending and find the nearest ATM.
Daily Budget
Budget travellers can get by on 800 to 1,500 THB a day. Mid-range travellers spend 2,000 to 4,000 THB. Bangkok and island resorts are pricier than the north.
Data cost: Carrier roaming often exceeds 300 THB a day, while a Roamix data plan typically costs a fraction of that for the same trip length.
Getting Around Thailand
Thailand mixes modern city transit with long-distance buses, ferries and domestic flights. Most booking and navigation now relies on a data connection, making a reliable eSIM essential.
BTS Skytrain and MRT in Bangkok
Signal is strong at all stations and on the trains. Use the Rabbit Line app or contactless bank card to tap in and out, with a connected phone for real-time route planning.
Grab rideshare and taxis
Grab is the dominant app in Thailand and requires an active data connection. Metered taxis are an alternative but Grab gives fixed prices and driver tracking.
Ferries and boats
Essential for island travel. There is often no signal on open-water crossings, so download ferry schedules and offline maps of your destination island before you board.
Domestic flights
The fastest way to reach Phuket, Chiang Mai or Ko Samui from Bangkok. A Roamix eSIM lets you manage mobile boarding passes and rebook if schedules change.
Regions & Travel
Thailand packs staggering variety into one country, from the rooftop bars of Bangkok to mountain villages near Chiang Rai and crystal-clear gulf beaches. Staying connected with a Roamix eSIM keeps navigation, ride bookings and live transit updates working as you move between these very different landscapes.
Best time to visit: November to February is cool and dry across most of the country and the best overall window. The Andaman coast is best from November to April, while the Gulf of Thailand coast peaks from July to October when the Andaman is wetter.
Bangkok and Central Thailand
The capital is one of Southeast Asia's most energetic cities, with the Grand Palace and Wat Pho, rooftop bars on Sathorn, the food stalls of Yaowarat Chinatown, the nightlife of Khao San Road, and the weekend chaos of Chatuchak Market all compressed into a megacity of 12 million.
Signal: Excellent 5G across all Bangkok districts. BTS Skytrain stations and MRT underground stations have strong in-station coverage. The expressways have reliable 4G throughout.
Chiang Mai and Northern Thailand
The cultural capital of the north, famous for its 300 temples, the Sunday Night Market on Wualai Road, the Doi Suthep mountain temple, and as a hub for trekking and elephant sanctuary visits. Pai, three hours north on Route 1095, has become a backpacker and digital nomad favourite.
Signal: Strong AIS 4G and 5G in Chiang Mai city and along the moat area. Route 1095 to Pai has AIS 4G on most bends. Deep jungle treks to hill tribe villages can go off-network, so download offline maps before heading out.
Phuket and the Andaman Coast
Thailand's largest island and its most developed beach destination. Patong, Kata, and Karon on the west coast have full resort infrastructure. The real Andaman magic is offshore: Koh Phi Phi, the Similan Islands, and the limestone karst bays of Phang Nga Bay.
Signal: Excellent AIS and True Move H 4G and 5G across Phuket. Koh Phi Phi and Koh Lanta have usable AIS 4G in populated beach areas. Similan Islands liveaboard boats go off-network once at sea.
Koh Samui and the Gulf Coast
The Gulf of Thailand's island trio: Koh Samui (biggest, most resort-developed), Koh Phangan (Full Moon Party capital), and Koh Tao (world-class diving). Hua Hin on the mainland is a quieter beach retreat popular with Bangkok weekenders.
Signal: AIS 4G covers Koh Samui, Koh Phangan, and Koh Tao's populated beach areas well. Koh Nang Yuan off Koh Tao has limited signal. Hua Hin has strong AIS 4G and 5G.
Chiang Rai and the Golden Triangle
The northernmost region of Thailand borders Myanmar and Laos. Chiang Rai is known for the White Temple (Wat Rong Khun), the Blue Temple (Wat Rong Suea Ten), and the remote hill tribe villages of the Mae Sai border area. The Golden Triangle at the confluence of the Mekong, Ruak, and Sop Ruak rivers is a short boat ride away.
Signal: AIS 4G in Chiang Rai city and along the main highway to Mae Sai. Remote border villages and mountain passes have intermittent signal. Download maps before heading north of town.
Hidden Gems
Doi Suthep hiking trail
mountain trailNorthern Thailand
A revered temple perched above Chiang Mai with sweeping views, reached by a popular forested hiking trail or by red songthaew minibus.
Signal: Good signal at the trailhead and near the summit temple, but sporadic on the trail itself through the forest.
Use your Roamix eSIM for navigation to the trailhead and to share photos from the summit, and download offline maps in case signal drops mid-trail.
Ko Tao
IslandGulf of Thailand
One of the world's most affordable and popular scuba diving certification destinations, with clear water and abundant marine life.
Signal: Decent 4G coverage across the main beach areas and dive schools, but signal disappears on open-water dive trips and hiking the interior.
A Roamix eSIM on the AIS footprint gives the strongest island coverage for booking dive trips, messaging and navigating between beaches.
Pai
mountain regionNorthern Thailand
A bohemian mountain town in a valley three hours from Chiang Mai, with a canyon walk, hot springs at Tha Pai, and a relaxed traveler culture. At 400 metres elevation, the temperature is genuinely cool in winter.
Signal: AIS 4G in Pai town and along the main street. Route 1095 between Chiang Mai and Pai (762 bends) has AIS 4G at switchback viewpoints. Deep jungle outside town drops to edge or no signal.
Pai guesthouses book out fast in December and January. Roamix data lets you secure Pai Circus Hostel or the wooden bungalows at Baan Krating Pai Resort from Chiang Mai before the bus journey.
Koh Lanta
IslandAndaman Coast
A quieter alternative to Phuket and Phi Phi. Long Beach has a full lineup of beach bars and restaurants without the party density. Old Lanta Town is a Muslim fishing community with some of the best fresh seafood in the Andaman.
Signal: AIS 4G on Long Beach, Klong Dao Beach, and the Old Town pier area. Southern beaches including Bamboo Bay have weaker signal. Download offline maps before exploring the southern tip.
Roamix data lets you book longtail tours to the Thalane limestone caves and kayaking day trips to Koh Mook's Emerald Cave, both of which operate from Koh Lanta piers and sell out in high season.
Sukhothai Historical Park
archaeological siteCentral Thailand
The first capital of the Thai kingdom, with dozens of medieval stupas, Buddha statues, and reflecting ponds spread across a tranquil park. Bicycle rental is the only way to explore.
Signal: AIS 4G throughout the historical park and Sukhothai town. Good coverage at most temple ruins.
The Sukhothai Historical Park app on your Roamix data includes audio guides for each major temple, saving you from hiring a tour guide at the gate.
Kanchanaburi and the River Kwai
city districtWestern Thailand
The most historically significant destination in Thailand for Western visitors. The Death Railway Bridge, the Thailand-Burma Railway (JEATH) War Museum, and the Hellfire Pass Memorial are deeply moving sites. The Erawan National Park waterfalls are among Thailand's most beautiful.
Signal: AIS 4G in Kanchanaburi town. Good coverage along the main River Kwai Noi bridge area. Remote jungle waterfall areas like Erawan National Park have no signal.
Erawan National Park has a visitor cap. Book entrance tickets online via the Thai National Park app using your Roamix data before driving the two hours from Bangkok.
Doi Inthanon National Park
National ParkNorthern Thailand
Home to Thailand's highest peak at 2,565 metres. The twin royal chedis (Naphamethanidon and Naphaphonphumisiri) set among mist-covered gardens are extraordinary. Waterfall season is October to November.
Signal: AIS 4G at the park entrance and summit area. Jungle trails between the twin chedis and the summit plateau have intermittent signal. Download offline maps before entering the park gates.
Doi Inthanon is 90 minutes from Chiang Mai and one of the most popular day trips in the region. Roamix data lets you check waterfall conditions and trailhead closures via the Royal Project Foundation website before heading out.
Koh Yao Noi
IslandAndaman Coast
Arguably the last unspoiled island accessible from Phuket. No major resorts, rubber plantations, and a quiet Muslim fishing community make it feel like Phuket 30 years ago. Sea kayaking through mangrove tunnels is the main activity.
Signal: AIS 4G in the main village and Ban Tha Kai pier area. Remote kayaking routes into the mangroves have intermittent signal.
Ferries from Phuket's Bang Rong pier run twice daily and sell out in high season. Book your Koh Yao Noi guesthouse using Roamix data in Phuket before boarding. The Six Senses and Paradise Koh Yao are exceptional but require advance booking.
Ayutthaya Historical Park
archaeological siteCentral Thailand
The former capital of the Thai kingdom, destroyed by the Burmese in 1767. The iconic image of Buddha heads entwined in banyan tree roots at Wat Mahathat is one of Thailand's most photographed sights. Only 80 km from Bangkok, it is the most accessible major historical site in the country.
Signal: Excellent AIS 4G and 5G throughout Ayutthaya. The historical park has full coverage.
Ayutthaya by bicycle or with a tuk-tuk driver for the day is the classic approach. Roamix data lets you identify which temples are open, check the sunset light direction for Wat Chaiwatthanaram, and book the 17:30 river dinner cruise on the Ayutthaya Princess.
Khao Sok National Park
National ParkSouthern Thailand
One of the oldest rainforests in the world, older than the Amazon, with dramatic limestone karsts rising from the Cheow Lan lake. Floating raft house accommodation on the lake is one of Thailand's most extraordinary experiences.
Signal: AIS 4G in Khao Sok village and at the Ratchaprapha Dam lake. Deep jungle trails inside the park have no signal. Download offline maps of the dam lake and main trails before arriving.
Raft house accommodation on Cheow Lan Lake books out months in advance, especially from November to March. Research operators including Krabok Kiri and Art's Riverview Lodge on your Roamix data and reserve well in advance.
Events & Best Seasons
Songkran Water Festival
FestivalNationwide, best in Chiang Mai and Bangkok Silom · April 13 to 15
Thailand's New Year celebration is the world's biggest water fight. Streets across the country turn into days-long soaking battles. Chiang Mai's moat area and Bangkok's Silom Road are the two epicentres of the chaos.
Network note
Networks handle the crowds well in cities, but expect slowdowns in the densest celebration zones such as Tha Phae Gate in Chiang Mai during the peak afternoon hours.
Roamix tip
Waterproof your phone before heading out. A dry bag is essential. Roamix data works through a waterproofed phone case for navigation in the crowd. Book accommodation at least three months in advance for Songkran in Chiang Mai.
Yi Peng Lantern Festival
FestivalChiang Mai · November 23 to 25, 2026
The release of thousands of paper sky lanterns over the Mae Ping River in Chiang Mai is one of the most photogenic nights on earth. Occurs simultaneously with Loy Krathong, when lotus-shaped floats with candles are released on the river.
Network note
Chiang Mai gets extremely crowded during Yi Peng. Expect congested networks near the main lantern release areas, especially around Maejo University on the mass-release night.
Roamix tip
The official mass release at Maejo University outside Chiang Mai requires tickets booked months ahead via the Yi Peng Lanna International organiser. Roamix data is essential for tracking ticket release dates, which sell out in minutes.
Loy Krathong
FestivalChiang Mai, Bangkok, Sukhothai · November 24 to 25, 2026
Thailand's Festival of Lights, where elaborately decorated floats (krathong) made of banana leaves, flowers, and incense are released on rivers and lakes. Sukhothai's celebration against the backdrop of ancient ruins is considered the most traditional.
Network note
Sukhothai fills completely during Loy Krathong and mobile networks can be congested around the historical park. Download the festival schedule before arriving.
Roamix tip
Sukhothai fills completely during Loy Krathong. Book accommodation in the historical park guesthouses or Sawaddiphong Hotel well in advance. Roamix data lets you track the festival boat race schedule and sunset timings at Wat Mahathat.
Full Moon Party
FestivalHaad Rin Beach, Koh Phangan · Monthly, around the full moon
The world's most famous beach party, running since 1985. Between 10,000 and 30,000 people gather on Haad Rin Beach for a night of music stages, fire shows, and luminous body paint.
Network note
Haad Rin Beach has AIS 4G coverage but the network gets congested when tens of thousands of attendees all upload photos simultaneously, so speed drops during peak midnight hours.
Roamix tip
Accommodation in Haad Rin books out weeks before each full moon. Book your Lomprayah ferry from Koh Samui or Chumphon on Roamix data well in advance. The 2026 dates track the lunar calendar.
Chiang Mai Flower Festival
CulturalChiang Mai · First weekend of February
A three-day festival celebrating the blooming season in northern Thailand, with elaborate flower-covered floats parading through the city and large floral arrangements in Suan Buak Hat Park.
Network note
Chiang Mai city has excellent AIS 4G and 5G coverage throughout the parade route on Nimman Road, with no significant congestion issues.
Roamix tip
The parade along Nimman Road takes place on the Saturday morning. Hotels in Chiang Mai old city fill for this weekend. Roamix data lets you track the official parade route map issued by Chiang Mai municipality a week before the event.
Vegetarian Festival (Tesagan Gin Je)
religiousPhuket Town and Trang · October, nine days
A Chinese Taoist festival of extraordinary intensity, where devotees in Phuket practice firewalking, body piercing with swords and skewers, and strict vegetarianism as acts of purification. Not for the faint-hearted but absolutely compelling to witness.
Network note
Phuket Old Town has strong AIS 4G and 5G coverage throughout the festival. Street processions are densely attended but network congestion is not typically severe.
Roamix tip
The main street processions in Phuket Old Town start at dawn and are genuinely challenging to watch. Roamix data lets you check the daily schedule of ceremonies at specific Chinese shrines, as the most intense rituals vary by shrine and day.
Bangkok Art Biennale
artsBangkok, citywide · October to February (biennial, next 2026 to 2027)
A major contemporary art event spread across Bangkok's historic venues including Wat Arun, the Grand Palace area, and warehouses in the Bang Rak riverside district.
Network note
Bangkok's city centre venues have excellent AIS 5G coverage, making it easy to stream exhibition guides and navigate between dispersed locations.
Roamix tip
The Bangkok Art Biennale app requires data to navigate the dispersed venues. Roamix data on AIS 5G in central Bangkok is fast enough to stream exhibition audio guides and check real-time venue opening hours.
Phuket Bike Week
SportsPatong Beach, Phuket · Late April, four days
Asia's largest motorcycle festival, drawing 100,000 bikers and spectators to Patong Beach for custom bike shows, concerts, and rides around the island.
Network note
Patong Beach has strong AIS 4G and 5G but networks can be strained at peak concert and parade times when 100,000 attendees are concentrated on the beachfront.
Roamix tip
Patong accommodation fills a month ahead for Bike Week. Roamix data lets you book the Kata Beach or Karon alternatives if Patong is sold out and navigate the bike parade route safely.
King Bhumibol Memorial Day
national holidayNationwide · October 13
A public holiday remembering King Rama IX, who passed in 2016 and remains deeply revered. Ceremonies occur at temples nationwide and at Sanam Luang in Bangkok.
Network note
Networks are unaffected by this holiday. Many businesses and government offices close, so use your Roamix data to check temple and attraction opening hours in real time.
Roamix tip
Many businesses and all government offices close. Plan your Bangkok sightseeing around the closures using Roamix data to check temple opening hours in real time.
Khao Phansa Candle Festival
CulturalUbon Ratchathani · July, three days
Marking the start of Buddhist Lent, Ubon Ratchathani in Isaan hosts one of Thailand's most spectacular and undervisited festivals, with enormous intricately carved wax sculptures paraded through the city on ornate floats.
Network note
Ubon Ratchathani city has reliable AIS 4G coverage throughout the parade route and central temple areas.
Roamix tip
Ubon Ratchathani is in the far northeast and most tourists miss this festival entirely. It is one of Thailand's most authentic and crowd-free major cultural events. Book your flight from Bangkok on Roamix data at least a month out.
Spring
March to May brings rising heat before the rains. Songkran in April is the cultural highlight of this season and well worth planning a trip around.
Summer
June to August is the wet season across most of the country, with daily afternoon downpours but fewer crowds and lower prices. The eastern gulf coast is generally drier during this period.
Fall
September and October are the wettest months overall, but the Andaman sea begins to calm by October, and Loy Krathong in November is spectacular.
Winter
November to February is the coolest and driest season and the most popular window to visit. Book accommodation and tours early during this peak period.
Remote Work from Thailand
Thailand is excellent for remote work, with cheap fast fiber and mobile internet in co-working cafes, a large digital nomad community and a low cost of living. Chiang Mai is arguably Southeast Asia's top digital nomad hub.
Urban 4G and 5G easily handle video calls and hotspot use. A Roamix plan with 20 GB or more covers a working week of calls and uploads alongside sightseeing.
Cafes in Chiang Mai's Nimman area and Bangkok's Silom district offer the fastest and most stable wifi for serious work sessions. Use your eSIM as a secure backup for sensitive tasks on public networks.
Get connected the moment you land in Thailand.
Get your Thailand eSIMLocal Tips for Thailand
Language
Thai script is used everywhere. A connected translation app that reads camera images is genuinely useful for restaurant menus and signs outside tourist areas.
Tipping
Tipping is appreciated but not obligatory. Round up restaurant bills or leave 20 to 50 THB for good service. Massage and spa workers appreciate a 50 to 100 THB tip.
Food & Dining
Thai street food is a highlight of any trip. From pad thai carts on Bangkok side streets to fresh seafood barbecues on beach islands, eating well and cheaply is effortless. Use a connected food app to find the best-reviewed local spots.
Transport
Grab is the go-to for safe, price-fixed rides in Bangkok and major cities. In smaller towns, tuk-tuks and songthaews are fun but negotiate the price before you get in.
Emergency Numbers
general
191
police
191
ambulance
1669
fire
199
Essential Apps
Grab
The dominant rideshare and food delivery app in Thailand, essential for safe and price-fixed taxi rides in Bangkok and major cities.
LINE
The default messaging app for locals and businesses across Thailand, used for bookings, tours and everyday communication.
Google Translate
Camera translation of Thai menus, signs and tickets is genuinely useful outside the tourist trail.
Safety & Health in Thailand
Thailand is generally safe for tourists, with the main risks being petty theft in crowded areas, road safety and occasional political demonstrations in Bangkok. Staying connected helps you check live advisories.
Keep your Roamix eSIM active to follow official travel advisories, use Grab instead of unmarked taxis for safer rides, and share your location with someone when heading to remote areas.
Health Note
Heat and sun are the biggest daily hazards. Dengue fever is present, so use repellent. Tap water is not safe to drink; always use bottled or filtered water.
Water Safety
Do not drink tap water anywhere in Thailand. Bottled water is cheap and widely available, and most hotels provide filtered drinking water.
Frequently Asked Questions
Thailand eSIM, connectivity, and travel
What is the best eSIM for Thailand?
Roamix is a strong choice for Thailand because it connects to the best available local network, including AIS which leads for island and rural coverage. You install it before you fly and it activates automatically on landing, with no SIM counter or paperwork.
Do I need a SIM card for Thailand?
You do not need a physical SIM. A Roamix Thailand eSIM gives you local-speed data without swapping cards, activates on arrival and avoids the queues at airport SIM kiosks. If your phone is eSIM capable, it is the simpler option by far.
What is the most affordable eSIM for Thailand?
Roamix offers Thailand plans that significantly undercut carrier roaming charges, with sizes from short city breaks to month-long stays. You pay only for the data you need rather than expensive daily roaming fees.
What is the best way to stay connected in Thailand?
A travel eSIM like Roamix on a local Thai network is the best combination of convenience and value. It avoids roaming bills, activates instantly, covers cities and islands, and works for Grab, maps and LINE from the moment you land.
Does an eSIM work on Thai islands like Ko Samui or Ko Tao?
Yes. Major islands including Ko Samui, Ko Tao and Ko Lanta have reliable 4G coverage in the beach and town areas. A Roamix eSIM on the AIS network gives the best island coverage for booking dive trips, messaging and navigation.
How do I set up a Roamix eSIM for Thailand?
Buy your plan on the Roamix Thailand eSIM page, install the eSIM over wifi before you fly, then enable data roaming on the Roamix line. It connects to AIS or True Move H automatically when you land, with no store visit needed.
Is my phone compatible with a Thailand eSIM?
Most phones from the last several years support eSIM, including iPhone XS and newer, Google Pixel 3 and newer, and recent Samsung Galaxy models. Your phone must be carrier unlocked to use a Roamix eSIM.
How much data do I need for two weeks in Thailand?
Most travellers covering Bangkok, Chiang Mai and islands over two weeks use 8 to 12 GB for maps, Grab, social media and light streaming. Choose 15 to 20 GB if you tether a laptop or take frequent video calls.
Do I need a visa to visit Thailand?
Nationals of 93 countries including the US, UK, EU, Australia and most of Asia enter Thailand visa free for 60 days. A Thailand Digital Arrival Card must be completed online before landing. Confirm current rules with the Royal Thai Embassy before booking.
Do I still need cash in Thailand if I have a connected phone?
Yes. Street food, markets, temples and many local restaurants are cash only. Keep at least 500 to 1,000 THB on you at all times. A connected Roamix eSIM helps you locate the nearest ATM and track spending through your banking app.
Can I use WhatsApp, LINE and Google in Thailand?
Yes. Thailand has an open internet with no restrictions on messaging, calling or social media apps. WhatsApp, LINE, FaceTime and Google all work normally on a Roamix Thailand eSIM without a VPN.
Is airport wifi at Suvarnabhumi enough or should I get a Thailand eSIM?
Airport wifi at Suvarnabhumi covers the terminal but ends at the doors. A Roamix eSIM keeps you online in the taxi queue, on the expressway and for the rest of your trip, which makes a big difference when you need Grab or maps immediately on arrival.
Will my eSIM work at Khao Sok National Park and the Cheow Lan Lake raft houses?
AIS 4G works in Khao Sok village and at the Ratchaprapha Dam lake area, which is enough to reach operators like Krabok Kiri and Art's Riverview Lodge for bookings. Deep jungle trails inside the park have no signal, so download offline maps of the dam lake and main trails before entering. A Roamix eSIM on AIS gives you the best available coverage in this area.
Does a Roamix eSIM work for the Yi Peng Lantern Festival and Loy Krathong in Chiang Mai?
Yes. Chiang Mai has excellent AIS 4G and 5G coverage throughout the city and the moat area. Expect some network slowdowns during the peak lantern release at Maejo University when tens of thousands of visitors are all online at once. Use your Roamix data to track ticket release dates for the official Yi Peng Lanna International mass release, which sells out in minutes.
Still have questions?
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Stay connected across Thailand with Roamix
Skip the SIM counter queue at Suvarnabhumi and land with local data already running. A Roamix Thailand eSIM activates automatically, covers the cities and the islands, and costs far less than carrier roaming.
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