Best Vietnam eSIM for 7 Days: Ha Long Bay & Hanoi 2026
If you're spending 7 days between Hanoi and Ha Long Bay, you need data that works on the water and in the city. Viettel's 5GB/day plan at $10 is the top pick, and we at simvietnam.telebox.vn recommend it. Here's why.
Coverage in Ha Long Bay vs Hanoi: Which carrier works best?
Ha Long Bay is a unique environment where network coverage varies significantly. Viettel has the best offshore coverage among Vietnam's carriers, making it the most reliable choice for cruise passengers and those visiting scattered islands like Ti Top or Bo Hon. Its 4G/LTE signal typically remains strong even when you're several kilometers from shore.
Vinaphone covers the central area of Ha Long Bay well, but its signal drops noticeably as you move farther from the tourist hub. Within Hanoi, all three major carriers—Viettel, Vinaphone, and Mobifone—offer robust 4G/LTE coverage. 5G is available in Hanoi's central districts, but for most travel needs, 4G speeds are more than sufficient for maps, messaging, and social media.
Mobifone provides adequate service in Hanoi but has weaker coverage in Ha Long Bay, especially on the water. If your trip involves a cruise or visits to remote karst islands, we recommend avoiding Mobifone for primary data use. For pure city travelers, any carrier works, but for a mixed itinerary, Viettel is the clear winner.
How much data do you need for a 7-day trip?
Typical usage for a 7-day trip includes navigation, social media, messaging, and occasional video calls. Most travelers use between 1 and 2 GB per day, which makes a 5 GB/day plan more than sufficient. If you plan to share your connection with one other person via hotspot, 5 GB/day is still comfortable.
Heavier usage, such as streaming video during a Ha Long Bay cruise, fits within a 5 GB/day cap as well. For reference, Netflix recommends about 1 GB per hour for standard definition and up to 7 GB per hour for 4K, but few travelers stream 4K on a boat. If you anticipate very heavy streaming or downloading, Mobifone offers a 7 GB/day plan, though with the coverage trade-offs mentioned earlier.
One practical tip: Download offline maps of Ha Long Bay and Hanoi before you depart. While data is abundant in the city, cellular speeds can be slower out on the bay. Having maps cached locally ensures you can navigate without interruption, even if the connection dips.
Our recommendation: Viettel 5GB/day for $10
The Viettel 7-day 5GB/day eSIM at $10 is the best balance of coverage and price for a combined Ha Long Bay and Hanoi trip. It gives you reliable offshore performance where it matters most, plus strong speeds in the city. For most travelers, this plan covers everything needed without overpaying.
If saving money is your priority, the Mobifone 7-day 7GB/day plan at $8 is cheaper and offers more data. However, its weaker bay coverage means you may struggle to stream or even load maps while on the cruise. For travelers spending all their time in Hanoi, Mobifone is a fine budget option, but not for the full itinerary.
Vinaphone's 10-day 5GB/day plan at $12 is worth considering if your trip extends beyond 7 days. It gives you three extra days for only $2 more than Viettel's 7-day plan. Global eSIM brands like Airola ride the same networks but typically charge a higher per-GB rate, so local store plans offer better value.
Installing your Vietnam eSIM before departure
We recommend installing your eSIM before you leave home. The activation process requires an internet connection, so doing it over Wi-Fi is much simpler than searching for a signal upon arrival. You'll receive a QR code via email; simply scan it in your phone's settings under 'Add Cellular Plan'.
Most modern smartphones support eSIM. Compatible models include iPhone XS and later (US, EU, Korean, and Japanese versions), Samsung Galaxy S20 and newer, Google Pixel 3 and newer, and recent Chinese flagships from Oppo, Xiaomi, and Huawei. An important exception: mainland China iPhones do not support eSIM at all, and Hong Kong/Macau iPhones also lack this feature. If you use one of those devices, you will need a physical SIM card instead.
Dual SIM functionality works seamlessly. Keep your home SIM active for calls and SMS while using the eSIM for data. In your phone settings, set the eSIM as the default data line. This way you stay reachable on your regular number without paying roaming charges for data.
FAQ
Can I use this eSIM on a Ha Long Bay cruise?
Yes. If you choose the Viettel eSIM, it works well on cruises thanks to Viettel's strong offshore coverage. Vinaphone and Mobifone plans may have patchier signal once you are far from shore.
What if I run out of data during my trip?
You can top up your eSIM or purchase a new plan from our store. Most plans offer daily data caps, so running out is unlikely with typical usage. Alternatively, use Wi-Fi at hotels and cafes.
Does the eSIM work on my Samsung Galaxy phone?
Samsung Galaxy S20 and newer models (excluding some regional variants) support eSIM. Check your phone's IMEI or settings for eSIM compatibility. If your Galaxy supports eSIM, it will work with our plans.
Can I keep my home number active while using the eSIM?
Yes. With dual SIM functionality, you can keep your home SIM active for calls and texts while using the eSIM for data. Just set the eSIM as your default data line in your phone settings.
When should I install the eSIM – before or after arriving in Vietnam?
Install the eSIM before departure while you have an internet connection. The activation requires internet, so it's easier at home. Once installed, it will connect automatically when you arrive in Vietnam and switch to a local network.