Vietnam's most reliable travel eSIM. Instant 4G on Viettel — Vietnam's largest network. Works from Ha Long Bay to the Ha Giang mountain loop.
The best eSIM for Vietnam is one that works instantly, avoids roaming fees, and doesn’t require local SIM registration. Ovosim connects you immediately on arrival with reliable 5G coverage.
Vietnam eSIM Configuration
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3GB/Day
5GB/Day
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Why smart travelers switch to Ovosim for Vietnam.
| Feature | OVOSIM | Airalo | Your Carrier Roaming |
|---|---|---|---|
| Cost (Standard Plan) | From €5.99 | €8.99 | $10/day+ |
| Network Speed | 5G / 4G+ Priority | Throttled | Varies |
| Setup | Instant QR | Manual | Automatic |
| Works with foreign cards | Yes | Limited | No |
| Available at airport | Before arrival | Sometimes | No |
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No surprises at the airport. Activate instantly on arrival.
Chat with actual humans if something goes wrong.
No hidden fees. No roaming charges. Period.
Ready in 3 simple steps.
Go to Settings > Cellular > Add eSIM and scan the QR code from our website
Name it 'Travel Data'. Set it to 'Secondary' so your main number still works.
When you land, turn on 'Data Roaming' for the eSIM line only.
Vietnam has three main carriers: Viettel (military-owned), MobiFone, and Vinaphone. Viettel controls over 50% of mobile subscribers and has built the most extensive rural infrastructure — critical for a country where the most spectacular landscapes are far from cities. The northern mountains (Sapa, Ha Giang, Cao Bang), the central highlands, and the remote fishing villages of the south all have better Viettel coverage than competitors. For the Ha Giang Loop specifically, Viettel is the only carrier with meaningful signal on the mountain passes.
Hanoi's Old Quarter is a maze of 36 ancient streets where addresses are confusing and motorbike traffic is dense. Google Maps is non-negotiable here. Viettel 4G covers the entire Old Quarter including the narrow alleys. The Hoan Kiem Lake area, Temple of Literature, and Ho Chi Minh Mausoleum district all have strong signal. Essential apps in Hanoi: Grab (for motorbike and car), Be (local Grab competitor, sometimes cheaper), and Foody for restaurant finding.
HCMC (Saigon) is one of the most navigationally complex cities in Asia due to its one-way systems, motorbike density, and constantly changing street-level detail. District 1 (Ben Thanh Market, Bui Vien backpacker street, Reunification Palace) has excellent 4G/5G. District 3, Binh Thanh, and the trendy Thu Duc creative district all have strong Viettel signal. The Cu Chi Tunnels (70km northwest of HCMC) are on the surface — Viettel 4G works at the tourist site. Download Google Maps offline for Ho Chi Minh City as backup for low-signal alleys.
Ha Long Bay cruises are the most popular tourist experience in Vietnam. Signal reality: Ha Long City and the cruise departure pier have strong 4G. Once your junk boat is in the bay among the limestone karsts, signal varies significantly. Some areas of the bay maintain 4G (the main cruise routes near Cat Ba Island); the outer, more remote karst areas drop to 3G or no signal. This is consistent across all Vietnamese carriers. Use onboard time to enjoy the scenery and upload photos when back at the pier.
The Ha Giang Loop is a 350km mountain motorbike circuit in Vietnam's northernmost province, bordering China. It passes through some of the country's most dramatic scenery — the Dong Van Karst Plateau Geopark (UNESCO), Ma Pi Leng Pass, and ethnic minority hill tribe villages. Viettel is the only carrier with consistent signal on this route. MobiFone and Vinaphone drop out on the mountain passes. For navigation on roads where a wrong turn leads to a cliff edge, having Viettel signal is not optional — it is the reason experienced travellers specifically request Viettel before doing the loop.
Hoi An Ancient Town (UNESCO World Heritage Site) has excellent Viettel 4G throughout the lantern-lit streets, the covered Japanese Bridge, and the tailoring district. Da Nang (the nearest major city, 30km north) has 5G in the city center. The Hai Van Pass between Da Nang and Hue — famous from the BBC Top Gear Vietnam special — has Viettel 4G on most of the pass. Hue's Imperial Citadel is well-covered. The train route between Da Nang and Hue (one of Asia's most scenic rail journeys) maintains 4G on the coastal cliff section.
Scan the QR code and connect immediately.
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OVOSIM offers the best value eSIM for Vietnam starting at €5.99. It connects to Viettel for 5G speed.
Plans start from €5.99 for 1GB. There are no hidden fees or roaming charges.
Yes, the eSIM activates instantly upon arrival. You will have 5G data immediately.
Ovosim connects to Viettel — Vietnam's largest carrier with the best rural and mountain coverage. This is the specific network recommended for the Ha Giang Loop, Sapa, and remote northern Vietnam.
Yes. Viettel is the only carrier with consistent signal on the Ha Giang mountain passes (Ma Pi Leng, Quan Ba Heaven's Gate). Competing carriers lose signal on the remote sections. Download offline maps as backup before starting the loop.
In Ha Long City and at the pier, yes. In the bay among the karsts, signal varies — the main cruise zones near Cat Ba have 4G; remote outer areas may have 3G or no signal. This affects all carriers.
Yes. Hoi An Ancient Town and Da Nang city both have strong Viettel 4G/5G. The Hai Van Pass coastal route between them maintains signal on most sections.
Vietnamese airport SIMs are already among the cheapest in Asia (VND 150,000–300,000 / €5.50–€11). Ovosim is competitively priced and saves you the passport registration queue. The main advantage is Viettel access in remote areas.
Yes in Sapa town. Viettel coverage extends into the Fansipan mountain area better than other carriers. On remote trekking paths between rice terraces and hill tribe villages, expect 3G with occasional dead zones in the deepest valleys.
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