The short verdict
For Greece, carrier choice matters especially for island travel. Cosmote (owned by Deutsche Telekom) is the largest Greek carrier and has the best coverage on the Aegean and Ionian islands — critical if you are island-hopping or visiting smaller destinations like Milos, Naxos, or Folegandros. Flysimio routes through Cosmote and offers the best price we found. Airalo also uses Cosmote but charges nearly double. Holafly uses Wind/Nova, which is strong in Athens and Thessaloniki but weaker on smaller islands.
Greece eSIM comparison table (2026)
| Provider | Plan | Price | Network | Refund |
|---|---|---|---|---|
| Flysimio | 5 GB / 30 days | $7.00 | Cosmote | 14-day full |
| Airalo (Flexiroam GR) | 5 GB / 30 days | $12.00 | Cosmote | Unused only |
| Holafly | Unlimited / 7 days | $15.00 | Wind / Nova | 24-hr unused |
| Nomad | 5 GB / 30 days | $9.50 | Vodafone GR | Unused credit |
| Saily | 5 GB / 30 days | $9.99 | Cosmote | Case by case |
Cosmote vs Vodafone GR vs Wind/Nova
| Carrier | Coverage | Best for |
|---|---|---|
| Cosmote | Best overall, best islands | Any trip including Aegean and Ionian islands |
| Vodafone GR | Strong in mainland cities | Athens, Thessaloniki, Patras |
| Wind / Nova | Good urban, weak on small islands | Athens and major tourist islands only |
Coverage across Greece's top destinations
| Destination | Coverage | Notes |
|---|---|---|
| Athens | 5G on all carriers | Excellent coverage throughout the city and port of Piraeus |
| Santorini | 4G on Cosmote and Vodafone | Strong in Fira and Oia; caldera viewpoints covered |
| Mykonos | 4G on all carriers | Full coverage of Mykonos Town and beaches |
| Crete | 4G on Cosmote and Vodafone | Heraklion and Chania strong; rural south coast weaker |
| Rhodes | 4G on Cosmote | Rhodes Town and north coast strong; rural interior patchy |
| Corfu | 4G on Cosmote | Strong in Corfu Town; north coast good |
| Milos, Naxos, Folegandros | 4G on Cosmote | Cosmote is the only carrier with reliable signal on smaller islands |
| Thessaloniki | 5G on Cosmote and Vodafone | Strong throughout the city |
Installing your Greece eSIM
- Buy before you fly — install on home Wi-Fi.
- Open the Flysimio email for the QR code.
- iPhone: Settings → Cellular → Add eSIM → Use QR Code.
- Android: Settings → Network & Internet → SIMs → Add SIM.
- Scan the QR code. Installation: under 30 seconds.
- Label it "Greece" and set it as your data line.
- Turn off Data Roaming on your home SIM only.
- Your phone connects to Cosmote when you land at Athens (ATH) or Thessaloniki (SKG).
Frequently asked questions
What is the best eSIM for Greece?
Flysimio on the Cosmote network is the best Greece eSIM in 2026. Cosmote has the widest coverage including smaller Aegean islands, and Flysimio offers the lowest price. Airalo uses the same network but costs nearly double.
Does eSIM work on Greek islands?
Yes, on Cosmote. Cosmote has the best Greek island coverage — including Santorini, Mykonos, Crete, Rhodes, Corfu, and smaller islands like Milos, Naxos, and Folegandros. Wind and Vodafone have weaker signals on smaller islands.
Does eSIM work in Santorini?
Yes. Santorini has 4G LTE coverage on Cosmote and Vodafone GR throughout Fira, Oia, and Akrotiri. The caldera viewpoints and main villages are well covered. Remote hiking trails on the southern tip may have reduced signal.
Is Holafly good for Greece?
Holafly is a good choice for Athens and major islands but uses the Wind/Nova network, which has weaker signal on smaller Aegean islands. For island-hopping, Cosmote (Flysimio) is the safer choice.
Does a Greece eSIM work on ferries between islands?
At port and close to shore, yes. On open water between islands, eSIM signal depends on distance from land. On short routes (Athens–Aegina, Piraeus–Heraklion), 4G is available for much of the journey. On longer open-sea crossings, signal drops mid-route.
Do I need a Greece SIM card or can I use eSIM?
eSIM is the better choice for most visitors. It is cheaper than airport kiosks, no SIM-swapping required, and your home SIM stays active. The only reason for a physical SIM is if your phone does not support eSIM.