Why Are There Connectivity Issues With North American Phones When Travelling - Even With 4G or 5G technology?
If you're a North American traveller who's ever landed overseas, popped in your SIM or eSIM, and found yourself struggling with poor coverage or no signal, you're not alone. Despite having a modern 4G or 5G phone, connectivity issues are surprisingly common.
Here's why.
1. Different Network Bands
North American phones - especially those from the U.S. and Canada - are often built to support specific LTE and 5G frequency bands optimized for local carriers like Verizon, AT&T, T-Mobile, Rogers, and Bell. However, international carriers use different bands for their networks. Even though 4G and 5G are global standards, the actual frequencies used vary significantly from region to region.
If your phone doesn’t support the specific bands used in countries like Japan, Australia, or many parts of Europe, your device may fall back to slower 3G or 2G networks - or fail to connect altogether.
📶 Common 4G LTE Bands by Region:
| Region | Common 4G Bands | Frequencies |
|---|---|---|
| North America | B2, B4, B5, B12, B13, B17, B66, B71 | 1900, 1700/2100, 850, 700 MHz |
| Europe | B1, B3, B7, B8, B20 | 2100, 1800, 2600, 900, 800 MHz |
| Asia & Australia | B1, B3, B5, B8, B28, B40 | 2100, 1800, 850, 900, 700, 2300 MHz |
📶 Common 5G NR Bands:
| Region | Common 5G Bands | Frequencies |
|---|---|---|
| North America | n2, n5, n41, n66, n71, n260, n261 (mmWave) | 1900, 850, 2500, 1700/2100, 600 MHz, 28 GHz, 39 GHz |
| Europe | n1, n3, n7, n28, n78 | 2100, 1800, 2600, 700, 3500 MHz |
| Asia & Australia | n1, n3, n28, n40, n78 | 2100, 1800, 700, 2300, 3500 MHz |
⚠️ Example: A U.S. phone relying heavily on band 71 (600 MHz) or mmWave bands (n260/n261) may not find equivalent support in Europe or Japan.
2. Locked Devices
Many North American phones are carrier-locked, especially if they were purchased under a contract. A locked phone won’t accept an international SIM or eSIM, even if the hardware is fully compatible with foreign networks. Always check that your device is unlocked before traveling or switching to a travel eSIM.
3. Missing eSIM Support
While eSIM adoption is growing, not all North American carriers or devices offer full eSIM functionality. Some phones sold in North America disable the eSIM feature entirely (custom firmware), or it may be locked to the original carrier. This can make it harder to take advantage of travel-friendly eSIMs like those from Airsims.com.au, which are designed for instant, hassle-free connectivity abroad.
4. 5G Isn’t the Same Everywhere
5G is not one universal experience. For example, the U.S. leans heavily on mmWave and mid-band 5G (with specific use of bands like n260 or n261), while countries in Europe and Asia may use different mid- and low-band frequencies. If your phone isn’t compatible with these international 5G bands, it may default back to 4G or slower networks.
💡 U.S. carriers use mmWave (e.g. band n261), which offers high speeds but extremely short range. This band is not used in most other countries.
💡 Europe and Asia have embraced mid-band 5G (e.g. band n78 at 3500 MHz), which your phone might not support if it was optimized for North America.
5. Outdated Firmware or Carrier Settings
Sometimes the issue isn't the network—it’s the phone itself. Carrier settings and firmware updates are often region-specific. A North American phone that hasn’t been updated properly may lack the settings needed to connect to international carriers or recognize eSIM profiles.
What You Can Do
✔️ Check Band Compatibility: Before traveling, confirm that your phone supports the cellular bands of your destination country. Use resources like GSMArena (3rd party company) or your manufacturer’s website.
✔️ Ensure Your Phone is Unlocked: Contact your carrier to unlock your device if necessary.
✔️ Use a Travel eSIM: Services like Airsims.com.au offer eSIMs tailored to regional networks, making it easy to get connected without physical SIM swapping. Easy refund and cancellation if it doesn't work.
✔️ Update Firmware and Carrier Settings: Keep your phone updated to ensure it has the latest configurations for global roaming.
Travel Connected With Airsims
Airsims makes staying connected abroad simple with affordable, country-specific eSIM plans. No roaming fees. No physical SIMs. Just scan, activate, and explore.
