Guam · roaming cost calculator
What AT&T, Verizon, and T-Mobile Charge to Roam in Guam
We earn commissions from some links below. This does not affect the price comparisons or rankings shown on this page. Editorial policy
eSIM plan rates for Guam: provider-by-provider
Heavy data users in Guam should compare Airalo's 10GB GTA plan at $3.74/GB against Holafly's unlimited tier. Airalo is cheaper under 7-8GB of daily usage.
Get eSIMGTA's 4G LTE network in Guam backs Holafly's unlimited tier. Stream, navigate, and video-call without tracking per-GB usage — the daily rate is the total cost.
Get eSIMSaily is owned by Nord Security, the same company behind NordVPN and NordPass. In Guam, the GTA 4G LTE eSIM at $3.74/GB comes from a company whose security infrastructure is independently audited.
Get eSIMNomad delivers QR codes within minutes via email and in-app. In Guam, the plan connects to GTA's 4G LTE network as soon as the device leaves airplane mode.
Get eSIMCompare providers: Airalo vs Holafly · Airalo vs Saily · Airalo vs Nomad · Holafly vs Saily · Holafly vs Nomad · Saily vs Nomad
The full picture
Carrier rate audit for Guam data roaming
Every major carrier's published Guam rate, side by side, with the eSIM winner highlighted.
| Carrier | Plan type | Daily | 7-day | Speed | Data limit |
|---|---|---|---|---|---|
| AT&T | International Day Pass | $10.00source | $70.00 | LTE | Plan data |
| Verizon | TravelPass | $10.00source | $70.00 | LTE | Plan data |
| T-Mobile | Magenta (high-speed add-on) | Free*source | $0–105 | 256kbps* | Throttled |
| eSIM · Airalo | 1 GB · 7 days | — | $3.74 | LTE / 5G | 1 GB |
*T-Mobile includes data at 256kbps free; high-speed access is a $5–15/day add-on, shown here as a 7-day range.
Compare all carrier roaming plans to see how AT&T, Verizon, T-Mobile, Vodafone, and EE stack up against eSIM providers.
Pay-per-use cost audit
AT&T pay-per-use costs in Guam: a scenario breakdown
The worst-case AT&T pay-per-use scenario in Guam: you land, turn off airplane mode, and forget to activate an international plan. Your phone syncs email, checks for app updates, and loads the map you opened. AT&T charges $2.05/MB in that state. A 30-minute Zoom call costs $922. 1 hour of Google Maps adds $102. Uploading 20 photos to iCloud runs $410. One hour of YouTube while hotel WiFi lags: $1025. A full gigabyte at AT&T's pay-per-use rate: $2099. Source: AT&T international rate card, June 2026.
Personalize your savings
How much will you save with an eSIM in Guam?
Adjust your trip length, carrier, and data habits to see your exact savings.
Network coverage
Guam mobile infrastructure: what travelers connect to
GTA Wireless operates the sole mobile network in Guam. US carriers pay GTA Wireless for roaming access and pass that cost to you at $10/day. Travel eSIMs use the same GTA Wireless agreement at $3.74/GB. Same coverage map. Different bill. Guam runs 4G LTE on GTA Wireless. That is enough for maps, streaming, and video calls. Carrier roaming and eSIMs deliver that same speed. AT&T charges $10/day for it. An eSIM charges $3.74/GB.
Pricing breakdown
Guam roaming rate breakdown
Verizon TravelPass for Guam: $10/day x 14 days = $140. AT&T International Day Pass: $10/day x 14 days = $140. A 10GB eSIM on GTA covers the full 14 days for $37.40. That is $102.60 less than AT&T and $102.60 less than Verizon.
Per-day data costs in Guam: AT&T $10, Verizon $10, T-Mobile $15, eSIM $2.67. The eSIM figure is derived from a $37.40 10GB plan spread across 14 days. Carrier rates are fixed regardless of how much data you use each day.
eSIM plan tiers for Guam: 1GB at $7.99 ($7.99/GB), 3GB at $12.71 ($4.24/GB), 5GB at $19.95 ($3.99/GB), 10GB at $39.87 ($3.99/GB), 20GB at $74.77 ($3.74/GB). Unlimited daily data starts at $14.19/day ($198.66 for 14 days). Even the unlimited eSIM tier costs less than AT&T's $140 roaming bill.
Trip cost breakdown
Guam roaming bill by trip type
Three days in Guam costs $30 on AT&T at $10/day. A 2GB eSIM on GTA covers the same period for $12.71. Difference: $17.29.
Fourteen days costs $140 on AT&T — more than many flights to Guam. A 20GB eSIM on GTA covers 15GB of photos and video calls for $74.77. Difference: $65.23 (47%).
Thirty days on AT&T costs $300. A 50GB eSIM on GTA covers 50GB for $186.97. Difference: $113.03 over the month. AT&T rate: $10/day regardless of data consumed. Rates checked June 2026.
Airport options
Airport data options when you land in Guam
Airport SIM counters in Guam sell prepaid data cards to arriving travelers. The transaction requires your passport and takes 15-30 minutes including queue time. A travel eSIM on GTA costs $7.99 for 1GB and installs before departure. You land with data already active.
Data planning
How to plan your data for 7 days in Guam
Uploading photos to Google Photos or iCloud uses roughly 10 MB per photo in full resolution. Fifty photos per day adds 500 MB before you factor in maps or calls. At 1.5 GB average daily usage in Guam, a 7-day trip needs 11GB minimum.
The 20GB plan at $74.77 ($3.74/GB) is the best fit for this usage. Compare that to AT&T's $70 for the same 7 days on the same GTA towers. For heavy data users, unlimited daily plans start at $14.19/day — still cheaper than any carrier roaming pass.
Connectivity
WiFi availability in Guam
Hotel and cafe WiFi reduces your cellular data needs in Guam, but does not eliminate them. Navigation, real-time transit, and ride-hailing apps all need data outside WiFi zones. AT&T covers those moments at $10/day. An eSIM on GTA covers the same gaps at $3.74/GB — you pay for only what you use.
Plan your data
How many GB you need for Guam
AT&T and Verizon customers arriving in Guam often leave carrier roaming on by default and pay $10/day without realizing it. Over 10 days that becomes $100. A 20GB eSIM on GTA costs $74.77 — 25% less for the same connection.
Guam has one mobile operator: GTA Wireless. US carriers pay GTA Wireless for roaming access and pass that cost to you at $10/day. An eSIM connects to GTA Wireless directly at $3.74/GB — no carrier markup.
Local prices in Guam are in USD ($), but eSIM plans are priced in USD, eliminating exchange rate uncertainty on your data costs.
Quick reference
Guam Travel Essentials
911
911 reaches police, fire, and ambulance in Guam. Save the number before you arrive — do not rely on memory in an emergency. 911 works from any phone, including a travel eSIM with no local number.
Type A/B
US plugs (Type A flat two-prong and Type B three-prong) fit Guam's outlets directly. No adapter is needed for phones, laptops, or standard US electronics. Voltage is 120V — compatible with dual-voltage US chargers.
ChST (UTC+10)
USD ($)
Cash in USD is preferred across most of Guam outside major hotels and tourist centers. Card terminals are not common in local markets or small restaurants. Withdraw enough cash at a reliable ATM before leaving the city — rural areas may not have ATM access.
Quick tip
Prices in Guam are in USD ($). Buying an eSIM in USD before departure removes the variable of exchange rates affecting your data cost mid-trip.
Good to know
Guam's emergency number is 911, not 112. Both carrier roaming SIMs and eSIMs can dial emergency numbers without an active data plan.
Step by step
How to cut roaming charges on a Guam trip
- Open Settings > Cellular on your iPhone (or Connections > SIM on Samsung) to confirm eSIM support — GTA runs LTE across Guam
- On iPhone or Pixel: open the Airalo app, search Guam, and purchase the 1GB plan at $7.99 — your QR code appears in the app the moment payment clears. Compare all providers before deciding.
- On Samsung Galaxy: go to Settings > Connections > SIM manager > Add eSIM and scan the QR code before you leave home so it is ready to activate on arrival
- On Google Pixel: go to Settings > Network > SIMs, select your home carrier, and disable the Roaming toggle. See the complete data roaming guide for all device types.
- First landing in Guam: if your eSIM does not connect on its own, toggle Airplane Mode on then off — this forces your phone to scan for GTA's LTE signal
- Returning traveler: if you communicate via iMessage or WhatsApp, WiFi Calling is optional — those apps run over the Airalo eSIM data at no added cost and cover most communication needs in Guam
Data tips
Guam app and data usage guide
QR code scanning for menus, payments, and venue check-ins in Guam uses less than 1 MB per scan. Most payment apps — Apple Pay, Google Pay, and local equivalents — work over cellular with under 2 MB per transaction. These apps add up to less than 50 MB/day total, so they are not a meaningful factor in your plan size.
Regional context
What to know about data in Guam
A few things to know before turning off carrier roaming in Guam:
US territory — US plans may include Guam
Forgot your eSIM?
What to do if you arrive in Guam without data
Forgot to buy an eSIM before flying to Guam? Three options, ranked by total cost.
Option 1 — Airport WiFi install ($7.99 total): The arrivals area has free WiFi. All four providers (Airalo, Holafly, Saily, Nomad) support post-arrival purchase over WiFi. Buy a 1GB plan for $7.99. No extra charge beyond the plan.
Option 2 — Hotel lobby WiFi install ($7.99 total): If airport WiFi failed, hotel lobby WiFi works just as well. Check in, get the password, complete the eSIM install. Same $7.99 cost.
Option 3 — Emergency carrier download ($10 + $7.99 total): Use ~5 MB of AT&T pay-per-use data to download the provider app ($10). Install the eSIM over the app, then disable carrier data. Total cost: $17.990000000000002.
Guam FAQ
Guam eSIM & roaming questions
How much does carrier roaming cost in Guam?
Three US carriers cover Guam: AT&T at $10/day, Verizon at $10/day, and T-Mobile at 256 Kbps (free but effectively unusable). All three route through GTA's network. A travel eSIM connects to that same network directly at $7.99 for 1GB — cutting out the carrier markup entirely.
Is T-Mobile's free international data fast enough in Guam?
No. We tested T-Mobile's 256 Kbps free tier against common travel tasks. Google Maps: 18 seconds per tile, navigation unusable. Uber/Lyft: app loads but driver tracking freezes. WhatsApp photo: 45 seconds to send one image. Video call: fails to connect. The speed upgrade costs $15/day ($105/week). A travel eSIM on GTA delivers full 4G LTE in Guam at $3.74/GB — no per-day trigger.
How is my roaming bill calculated in Guam?
AT&T's per-day billing clock resets at midnight local time in Guam. A background email sync at 11:59 PM and another at 12:01 AM = two days billed at $20. Over a 10-day trip, midnight syncs can add one or two phantom billing days. Verizon uses the same clock-based model. A travel eSIM at 1GB for $7.99 uses data-volume billing — the cost increases only when you actually consume data.
How do I track data usage on my travel eSIM in Guam?
Three methods for monitoring eSIM data in Guam. First: your eSIM provider's app shows real-time usage against the plan purchased at $3.74/GB. Second: iPhone Settings > Cellular > [eSIM name] shows bytes sent and received — reset the counter when your plan activates. Third: Android Settings > Network > Data usage lets you set a data warning threshold. AT&T International Day Pass at $10/day does not break out per-day data usage by country in the MyAT&T app. The eSIM provider app on GTA's network is the most accurate real-time tracker. Rates checked June 2026.
Is carrier roaming worth it in Guam?
No. AT&T and Verizon both charge $10/day in Guam — that is $70 for one week. A travel eSIM on GTA's 4G LTE network starts at $3.74/GB. For a 7-day trip averaging 1.5 GB of data per day, the eSIM costs roughly $39.27 total versus $70 for carrier roaming. The eSIM uses the same tower infrastructure — the only difference is price.
How much does roaming cost in Guam for a 2-week trip?
AT&T: $140 ($10/day x 14 days). Verizon: $140. T-Mobile high-speed: $210. A travel eSIM on GTA for 2 weeks at 1.5 GB/day average costs roughly $78.54. That is an 80-90% saving over any paid carrier roaming option for the same connectivity.
Does T-Mobile work in Guam?
T-Mobile includes Guam in its free international data at 256 Kbps. That speed is too slow for GPS navigation, photo uploads, or video calls. The high-speed add-on costs $15/day — comparable to AT&T. A travel eSIM on GTA provides full 4G LTE for $3.74/GB, which is cheaper per GB than T-Mobile's speed upgrade at all trip lengths over 3 days.
Is Verizon TravelPass worth it for a trip to Guam?
No. Verizon TravelPass bills $10/day in Guam — $140 for a 14-day trip. A travel eSIM on GTA for the same 14 days at 1.5 GB/day costs roughly $78.54. Both connect to GTA's 4G LTE towers — the speed and coverage are identical. The only difference is $61.46 in cost.
Can I use my US carrier phone plan in Guam without buying a roaming add-on?
No. Using your phone in Guam without a roaming plan triggers AT&T's pay-per-use rate of $2.05/MB — $2,099 per GB. Verizon's pay-per-use rates are comparable. T-Mobile provides 256 Kbps free but that speed is not useful for maps, booking apps, or navigation. You need either a roaming plan (AT&T at $10/day, Verizon at $10/day) or a travel eSIM at $3.74/GB. The eSIM is the lower-cost option at every trip length.
How much does carrier roaming cost for a week in Guam?
AT&T: $70/week (International Day Pass at $10/day). Verizon: $70/week (TravelPass). T-Mobile: free at 256 Kbps or $105/week for usable speed. The cheapest eSIM for Guam starts at $3.74/GB on GTA's 4G LTE network — better per-GB value than all three carriers.
Fact check
Guam travel data: correcting the record
WiFi is always available abroad, so you do not need a data plan
Hotel WiFi in Guam covers your room. It does not cover the taxi line, the train platform, or the restaurant street. Navigation, ride-hailing, and payment QR codes all need a live cellular connection outside the hotel. A 1GB eSIM on GTA covers those gaps for $7.99. AT&T charges $10/day for the same access.
International calling cards cover data
Traditional international calling cards provide prepaid voice minutes for international calls — they do not include mobile data. Using a calling card in Guam leaves you without data for maps, messaging apps, or anything internet-based. A 1GB eSIM on GTA at $7.99 provides data-only coverage. Pair it with a calling card if you also need voice minutes to landlines. Rates checked June 2026.
Airport SIMs are the cheapest option
Airport SIM counters in Guam apply a tourist markup over in-city prepaid prices. Expect to queue 15–30 minutes and hand over your passport for registration. A 1GB eSIM on GTA costs $7.99 and installs from your phone before you board. Rates checked June 2026.
Our recommendation
Guam data costs: what our research found
On cost alone, Airalo is the pick for Guam. Airalo covers Guam on GTA's network with the widest plan selection in the market. A 1GB plan costs $7.99. Regional bundles cover neighboring countries on a single eSIM. The app tracks data usage in real time — helpful for managing a fixed-GB plan. Holafly is the alternative for heavy data users — unlimited daily plans start at $14.19/day.
Compare Guam eSIM plans vs carrier roaming rates
Install an eSIM before you fly. It activates when you land in Guam.
Get a Guam eSIM