Getting Online in Cambodia: SIM Cards and eSIMs for American Travelers

The best providers, plans, and prices for 2026

Cambodia has three main mobile networks and a healthy field of travel eSIM apps. You do not need to overthink it — any of the big three local carriers will serve you well on a tourist itinerary, and the well-known eSIM apps all run on those same networks under the hood. What follows is what actually matters when you choose.

On the local side, the big three are Cellcard, Smart, and Metfone. Smart and Cellcard have the strongest reputations with travelers for coverage in Phnom Penh, Siem Reap, and the southern coast, with reliable 4G across the main tourist routes and growing 5G in the cities. Metfone, backed by Vietnam's Viettel, has the widest rural reach if you are heading well off the standard loop. Tourist SIM bundles from any of them typically land in the $5 to $15 USD range and bundle a big chunk of data with a validity window that comfortably covers a 1-to-2-week trip.

On the eSIM side, Airalo is the most popular all-rounder and usually the best value, with small data packs that suit a short trip. Holafly leans toward unlimited-data plans for heavier users who do not want to count gigabytes. Nomad and aloSIM sit in the same competitive bracket and are worth a quick price check. Expect to pay a few dollars more than a local SIM for the same data, which buys you the convenience of arriving already online with no counter, no passport registration at a kiosk, and no SIM swap.

A note on data sizing so you do not overpay or run dry: maps, messaging, ride apps, and web browsing sip data, while video streaming and uploading lots of photos and clips drink it. For a typical 1-to-2-week trip on Wi-Fi at your hotel each night, somewhere around 5 to 15 GB is plenty for most travelers. If you plan to stream or hotspot a laptop heavily, lean toward an unlimited eSIM plan or a larger local bundle rather than topping up repeatedly.

How to buy and activate, step by step

The mechanics are easy either way, but they happen at different times — the eSIM before you fly, the local SIM after you land. Knowing the steps in advance means no fumbling at the gate or at the kiosk.

1. 1
   Check and unlock your phone

   Before you leave the US, confirm your phone is carrier-unlocked, and for an eSIM that it is eSIM-capable, because you cannot fix a locked phone after you land.

2. 2
   eSIM: buy and install on Wi-Fi at home

   Pick a Cambodia data plan in an app like Airalo, Holafly, or Nomad, pay, and scan the QR code to install the eSIM days before you fly.

3. 3
   eSIM: set activation on arrival

   Choose the option to activate when the eSIM first connects to a Cambodian network, and keep your US SIM on for calls and two-factor texts.

4. 4
   Local SIM: bring your passport to the counter

   After immigration, visit a carrier kiosk in arrivals and show your passport, since Cambodian law requires every SIM to be registered to it.

5. 5
   Local SIM: pay and let staff set it up

   Tell them your trip length, pay in USD or riel, and they insert and test the card on the spot in about five minutes.

6. 6
   Keep your US SIM safe

   If you swapped in a physical SIM, store your US SIM and ejector pin somewhere safe so you can switch back for the flight home.

Setting up an eSIM before you fly

Do this at home on Wi-Fi, not in the airport scramble. Download your chosen eSIM app, pick a Cambodia data plan that fits your trip length, and pay. The app sends you a QR code; install the eSIM by scanning it in your phone settings, then choose whether to turn it on now or on arrival. Set your US physical SIM to keep handling calls and texts so your number and two-factor codes still work, and switch your default mobile data line to the new Cambodia eSIM. Most plans let you set activation to begin when the eSIM first connects to a network in Cambodia, so you can install days ahead without burning your data window.

Buying a local SIM after you land

Once you clear immigration, you will see carrier kiosks in the arrivals area, and there are phone shops everywhere in town if you would rather wait. Bring your passport — Cambodian law requires SIMs to be registered to a passport, and the staff will photograph or scan it and set the card up for you on the spot. Tell them how many days you are staying and roughly how much data you want, pay in USD or local riel, and they will insert and test the SIM before you leave the counter. Keep your US SIM card and its ejector pin somewhere safe so you can swap back when you fly home. The whole thing usually takes about five minutes.

Whichever route you take, the registration step is exactly why your passport matters at both ends of the trip — it is the same document tied to your eVisa and your e-Arrival Card, so keep it on you, not buried in your checked bag. If you want the full landing-day sequence, from immigration to SIM to taxi, our rundown of things to know before your first trip to Cambodia walks through what to do in what order so nothing trips you up at arrivals.

Coverage, Wi-Fi, and staying connected on the ground

Mobile coverage across the places most Americans actually go is genuinely good. Phnom Penh, Siem Reap, Sihanoukville, Kampot, and the islands close to the coast all have solid 4G, with 5G expanding in the major cities. You will get a strong signal at Angkor Wat and the main temple complex, along the highways between the big destinations, and in nearly every town with a tourist presence. The further you push into remote provinces and deep countryside, the more it thins out — that is where Metfone's rural reach can edge ahead — but on a standard first-trip itinerary you will rarely be without a usable connection.

Wi-Fi is widespread as a backup and a data-saver. Hotels, guesthouses, cafes, restaurants, and bars almost all offer free Wi-Fi, and it is generally fine for messaging, browsing, and uploading photos at the end of the day. The practical play is to lean on hotel and cafe Wi-Fi for the heavy stuff — backing up photos, video calls home, downloading maps for the next day — and use your mobile data for getting around, ride apps, and staying reachable while you are out. That combination stretches even a modest data plan a long way.

One spot worth planning for is the airport itself, where you may want to be online before you have bought a SIM or activated an eSIM. Most travelers either land on a pre-installed eSIM or jump on the terminal Wi-Fi to find their ride — our step-by-step Techo International airport arrival guide covers what to expect the moment you step off the plane, including where to get connected as you move through the terminal.

Mistakes to avoid (and a quick pre-flight checklist)

Almost every connectivity problem Americans hit in Cambodia traces back to something that could have been settled before takeoff. None of these are hard to avoid once you know them.

• A carrier-locked phone. If your US phone is locked to Verizon, AT&T, or T-Mobile, neither a local SIM nor an eSIM will work. Ask your carrier to unlock it before you leave — you cannot fix this once you land.
• No eSIM support. Older phones and some budget models do not support eSIM at all. Check your phone settings for an eSIM or "add cellular plan" option before you buy one; if it is missing, go with a local SIM instead.
• Letting roaming switch on by default. If you do nothing, your US carrier may auto-enroll you in a $10-plus daily roaming pass. Turn off data roaming on your US SIM line and route data through your eSIM or local SIM instead.
• Forgetting your passport for a local SIM. Cambodian law requires passport registration to buy a SIM. Show up at the counter without it and you cannot complete the purchase.
• Losing your US SIM. If you swap in a physical local SIM, store your US SIM and the ejector pin somewhere safe so you can switch back for the flight home.
• Buying way more data than you need. With hotel and cafe Wi-Fi everywhere, most travelers comfortably get by on a modest plan. Start smaller; you can almost always top up.

Sort connectivity the way you sort the rest of the trip — a little before you fly, the rest on landing day. Get your phone unlocked and your eSIM installed (or your plan to buy a local SIM decided) before you leave, and the airport becomes a five-minute formality. If you want to see where the SIM stop fits into a full route through the country, our 10-day Cambodia itinerary for first-timers sequences arrival, Angkor, Phnom Penh, and the coast day by day.

Connectivity is the easy part; the one thing to lock in first is the visa. A Tourist eVisa is $80 USD all-in and a Business eVisa is $90 USD, both approved in 3 business days, delivered as a printable PDF by email, with free resubmission if Immigration flags a correction and US-timezone support if you get stuck. When your dates are set, apply for your Cambodia eVisa, then set a reminder for the e-Arrival Card in the week before you fly.