Cellcard vs Smart Axiata vs Metfone, what has signal at Angkor Wat and around Siem Reap, why the guys selling SIMs at the border aren't worth stopping for, and roughly how much data you'll burn through.
Networks
Cellcard · Smart Axiata · Metfone
Best network
Smart Axiata — widest general coverage
Currency
KHR (Riel) — USD widely accepted
Border SIM sellers
Skip them — overpriced, capped data
Why skip the airport counter and the border hustle
Both airport counters, Siem Reap and Phnom Penh, are fine. Ten minutes, passport out, sorted. It's the land crossings that get annoying. Walk across at Poipet from the Thai side, or through one of the Vietnam checkpoints near Bavet, and there's a small crowd waiting with SIM cards fanned out like playing cards, all promising "unlimited data" for a price that somehow doubles the second they clock you're a tourist fresh off an overnight bus with no local currency yet.
A travel eSIM sidesteps both
Turn it on over Wi-Fi before you fly, or before the bus pulls up to the checkpoint, and you're already connected on the other side. No standing around comparing prices with a stranger holding a fan of SIM cards through your bus window.
Cellcard vs Smart Axiata vs Metfone
Network
Strengths
Best for
Smart Axiata
Largest subscriber base and broadest general coverage; strong in Siem Reap, Phnom Penh, and the coast; the network most international eSIM providers default to
Full Cambodia circuit including islands and coast
Cellcard
Cambodia's original network with a loyal following and decent reach in some rural provinces, though it has lost ground to Smart in recent years
Backup option or provinces where Smart is weaker
Metfone
Vietnamese-backed (Viettel) network with solid pricing and reasonable urban coverage
Budget local SIMs; less commonly used by eSIM providers
Coverage by destination
Siem Reap town
Full bars around Pub Street and the night markets, no surprise really, since half the tuk-tuk bookings in town happen over Telegram now. Easily the most connected corner of the country.
Angkor Wat & the temple complex
Better than you'd expect for a jungle temple site — Angkor Wat itself, Bayon, and Ta Prohm (the tree-root one from Tomb Raider) all hold a solid signal. Out at Banteay Srei or Beng Mealea it thins a bit, but it doesn't vanish.
Phnom Penh
Strong 4G citywide, from the Royal Palace and riverside promenade to the Russian Market. The capital has the country's densest tower coverage by a wide margin.
Battambang
Good coverage in town, including along the bamboo train route just outside the centre. This laid-back city gets less tourist traffic than Siem Reap, but the network doesn't suffer for it.
Kampot & Kep
Solid 4G through both riverside towns. The pepper plantations outside Kampot and the Bokor Hill Station drive get patchier the higher you climb — the old French hill station itself has weak, inconsistent signal.
Sihanoukville
Decent coverage in the town centre, though much of the beachfront has been reshaped by ongoing construction in recent years. Ferry departure points for the islands are well covered.
Koh Rong
Koh Touch has good Smart and Cellcard signal — it's the main village, so that tracks. Wander to the far side of the island and it gets spottier fast, which more than one bungalow owner has turned into a selling point rather than apologizing for.
Koh Rong Samloem
Fewer towers than its bigger neighbor, so weaker across the board. Saracen Bay usually holds a bar or two. The more tucked-away coves often just don't.
How much data do you need in Cambodia?
It's mostly logistics, not sightseeing, that eats the data here. Messaging your tuk-tuk driver on Telegram to confirm a 4:30am pickup, checking which minibus actually goes to Battambang today, or holding your phone up to a menu with no English on it and hoping the camera translation guesses the dish right. Then there's the photo-taking — Angkor Wat at sunrise is basically three hundred people all trying to get the same reflection shot in the pond before the person behind them steps into frame, and everyone's uploading proof by 6am.
Trip type
Recommended data
4-day Siem Reap + Angkor trip
4–6 GB
1-week Siem Reap + Phnom Penh
6–8 GB
10-day trip adding Kampot or the coast
8–12 GB
2-week circuit including Koh Rong
10–14 GB
Remote work / digital nomad (Phnom Penh based)
30–50 GB per month
Angkor sunrise tip
Download your Angkor temple map offline before your first pre-dawn tuk-tuk ride — the ticket checkpoint outside the complex gets crowded fast and it's easier to confirm your driver's pickup spot on a saved map than to rely on searching for it half-asleep at 4:45am.
Frequently asked questions
What is the best esim for Cambodia?
Smart Axiata covers more ground than the others, especially once you're off in Siem Reap, Phnom Penh, or down on the coast — it's also just what most eSIM providers default to anyway. Keep Cellcard in mind as a fallback for a handful of rural provinces where it still edges Smart out.
Is Angkor Wat covered by mobile signal?
Yes, more than you'd guess for a temple complex swallowed by jungle. Angkor Wat, Bayon, and Ta Prohm all run solid 4G. Push out to Beng Mealea and it gets thinner, though it doesn't fully disappear.
Should I buy a SIM from a vendor at the Cambodia border?
Better not to. Border-crossing vendors at Poipet and similar checkpoints often oversell data caps or push older stock at tourist-inflated prices. A travel eSIM bought ahead of time is already working the second you cross.
Is there phone signal on Koh Rong island?
Koh Touch, the main village, holds a decent signal. Head to the far-side beaches or over to Koh Rong Samloem and it drops off — a handful of the more remote bungalows there are basically unreachable, and some of them are happy to advertise it that way.
How much data do I need for a Cambodia trip?
A 4-day Siem Reap and Angkor trip needs about 4–6 GB. A longer 10-day trip adding Phnom Penh and the coast needs 8–12 GB, and a full 2-week circuit including Koh Rong runs closer to 10–14 GB.