Check your exact phone and carrier lock before paying
Check the full model and regional version, eSIM support and whether another carrier’s SIM can be used. Apple’s iPhone check is Settings → General → About, then look for “No SIM Restrictions” under Carrier Lock. For Android, use the manufacturer’s instructions for the exact model. If eSIM is unsupported, check whether the phone has a usable physical SIM slot and is unlocked. Resolve compatibility before buying rather than assuming a familiar model name is enough.
Ask separately about data, calls and SMS
eSIM describes the SIM format, not whether a plan includes a Vietnamese number, voice calls or SMS. A data plan may suit maps and messaging apps; local calling needs a separate check. Before comparing offers, note your trip length, expected usage and whether you want to share a hotspot. Ask about total versus daily data, what happens after the allowance, top-ups and expiry. A “30-day” label alone does not promise unlimited high-speed data every day.
Use official channels and the current identity-check process
Viettel’s tourist portal currently asks for a passport image, a portrait and an email address; its tourist guidance also tells counter customers to bring the original passport. Photography, upload and signing steps can differ by channel, so follow the current process where you buy. Verify the official website or service counter before sharing documents, and read the order, privacy and service terms. Keep passport images, activation QR codes and one-time codes out of public groups. ABIN’s trip enquiry form does not need them.
Confirm the all-in price and when validity starts
Viettel’s 2025 tourist article separated the package fee from the SIM price, so an old advertised plan price is not today’s all-in quote. Confirm SIM or eSIM fees, the package, taxes, renewal arrangements and cancellation or refund limits at purchase. Ask which event starts validity: purchase, installation or activation. Do not assume these are interchangeable. If buying before departure, establish what can be done early and what must wait until arrival.
After installation, select the intended data line
Viettel’s eSIM instructions show adding a plan from the phone’s cellular or SIM-management menu and scanning the carrier’s QR code; labels vary by operating system. Have working Wi-Fi and order details available, then follow that provider’s activation steps. With dual SIM, label the lines clearly and check which supplies mobile data and which handles calls. Enable data roaming only as your chosen plan instructs, not across every line. Confirm any home-line call, SMS and roaming charges with your home carrier.
Turn off Wi-Fi for a real mobile-data test
ABIN suggests briefly disabling Wi-Fi and loading a map and a new webpage before leaving, then testing the communication features you actually need. If calling is included, confirm the number and dialling method; test hotspot sharing if it matters. Ask how to check remaining data, expiry and support, and keep the receipt and plan name. If there is signal but no internet, check the selected data line and provider settings first. Do not immediately delete the eSIM: reinstall rules can differ. Save your hotel and pickup details offline before arrival as a fallback.
Further reading and sources
These sources support location and background information. The itinerary and checklists are planning suggestions; confirm opening arrangements, prices and booking conditions separately.
Next, explore venues and routes
- Tan Son Nhat arrival and pickup checks
- Entry checks and offline documents
- Before flying: power banks and liquids
- Once connected: practical checks before a Grab ride
Once you have dates, group size and preferences, send ABIN the details you want to confirm.
Discuss your trip with ABIN