Athens has operator desks in arrivals. The island airports mostly do not, which matters because plenty of people fly straight to Santorini, Mykonos or Crete and never pass through Athens at all.
Telekom (the old Cosmote), Vodafone or Nova?
Three national networks: Telekom, Vodafone Greece and Nova. Telekom is the old Cosmote, renamed on 8 September 2026, so your phone may now show TELEKOM.GR where older guides say Cosmote. Nova is the network that used to be called Wind.
All three cover the main islands. On smaller ones, one network can be strong where another is weak, so an eSIM that can use more than one network gives you a fallback.
Can you buy a SIM at Athens or the island airports?
At Athens Eleftherios Venizelos, ATH, Vodafone sells its tourist SIM from a kiosk in the airport, according to its own tourist page. Nova sells its FREE2GO tourist packs in Nova stores and at selected airports.
The island airports are a different story. Santorini, Mykonos and Rhodes get very busy in summer, and we could not find a phone shop the networks list at any of them. If you are flying straight to an island, do not plan on buying a SIM when you land.
Island arrivalsIf your itinerary is fly straight to an island, then ferry hop, buying locally is the weakest plan of all. You arrive somewhere small, at peak season, with limited or no provision, needing data immediately for your transfer.
Do you need a passport for a Greek SIM card?
Yes. Greece requires ID for a prepaid SIM. Law 3783/2009 says the line cannot be switched on until the operator has your identity details, and for visitors that means a passport. Nova's tourist packs ask you to photograph your ID and sign a short declaration.
How much a SIM card costs at Athens airport
| Option | Rough cost | Time | Passport needed |
|---|---|---|---|
| Vodafone kiosk at Athens airport | Tourist pack, price not shown online | Depends on the queue | Yes |
| Nova FREE2GO tourist pack | €15 for 7 days, €20 for 15 days | A Nova store visit | Yes |
| Island airport | Do not count on it | If there is a shop at all | Yes |
| Travel eSIM | from $1.29 | Done at home, before the island flight | No |
Nova's packs are generous. €15 buys 100 GB for 7 days and €20 buys 250 GB for 15 days, with unlimited minutes to Greek numbers. Our Greece plans start at $1.29, with 5 GB over 30 days at $3.33 and 10 GB over 30 days at $5.99, and every island is on the same plan. For a normal holiday that is less money and no store visit. If you stream all day, the Nova pack is the better deal.
What happens to your signal on the ferries
This is the part nobody warns you about, so here it is plainly.
You keep signal near shore and lose it in open water. That is true of every network, including a Greek one, and no SIM or eSIM will change it. On the long crossings from Piraeus to Crete or Rhodes, expect substantial stretches with nothing at all.
Some larger ferries sell WiFi on board, but do not plan around it.
The practical answer is simple: download your tickets, maps, podcasts and anything you want to read before you board, not while you are waiting at the port with everyone else doing the same.
Why is data slow on the Greek islands in August?
Greek islands carry many times their normal population in August. The networks were built for the resident population plus a reasonable season, not for the peak fortnight.
So in August you will see slower speeds on Santorini, Mykonos and Paros regardless of which network or which seller you used. This is congestion, not a fault with your SIM, and buying a local SIM does not exempt you from it.
Flying straight to an island? Install before you go
An eSIM installs at home over your own WiFi, sits switched off until you land, and connects while the plane taxis. For an island arrival that is worth considerably more than it is in a capital city, because there may be no desk to queue at anyway.
Ours runs on Vodafone Greece and Nova, the network that used to be called Wind, both on 5G. One profile covers the mainland and every island, and the days only start counting when it first connects in Greece.
Does your home plan already work in Greece?
An EU phone plan already works in Greece, islands included, on your normal allowance, so you can skip the desk and the eSIM. The one trap is near the Turkish coast: on Rhodes, Kos, Samos and Symi your phone can latch onto a Turkish mast, and Turkey is outside EU roaming. Our guide to the Turkish mast problem shows the two minute fix.
Coming from the US, Canada, Australia or Asia, you will usually pay a daily roaming fee, so you do need something. UK plans vary by network, so check yours.
Signal on Crete, the Cyclades and the mainland
- Athens: 5G across the city and in the metro.
- Thessaloniki and Patras: 5G in the centres.
- Crete: strong in Heraklion, Chania and Rethymno, thin on the Lasithi plateau and in the Samaria gorge.
- Santorini and Mykonos: good, but congested in peak August.
- Rhodes and Corfu: strong on the coast, weaker inland.
- Smaller Cyclades: 4G in ports and villages, patchy elsewhere.
- Ferries: signal near shore, nothing in open water.
Athens airport and island SIM questions
Can I buy a SIM card at Athens airport?
Yes. Vodafone sells its tourist SIM from a kiosk at Athens airport. Bring your passport, because Greece requires ID for prepaid SIMs. For comparison, Nova's FREE2GO tourist packs cost €15 for 7 days or €20 for 15 days.
Can I buy a SIM at Santorini or Mykonos airport?
Do not count on it. The island airports get very busy in summer, and we could not find a phone shop that the networks list at them. If you fly straight to an island, buy in a town phone shop or install an eSIM before you leave home.
Does mobile data work on the ferries in Greece?
Near shore yes, in open water no. You lose signal on the longer crossings such as Piraeus to Crete or Rhodes, and that applies to every network including Greek ones. Download tickets, maps and anything you want to read before you board. Some larger boats sell WiFi on board, but do not plan around it.
Which network has the best island coverage in Greece?
It depends on the island. All three cover the main ones, and on smaller islands one network can be strong where another is weak. An eSIM that can use two networks gives you a fallback, which is why ours runs on both Vodafone and Nova.
Why is my data slow on the Greek islands in August?
Congestion. The islands carry many times their resident population in peak August and the networks were not built for that peak. Speeds drop on Santorini, Mykonos and Paros regardless of which network or seller you used, and buying a local SIM does not exempt you.
Sources
- Law 3783/2009 on identifying mobile customers
- Vodafone Greece tourist SIM
- Nova FREE2GO tourist packs
- Deutsche Telekom: COSMOTE TELEKOM becomes Telekom
- Your Europe: mobile roaming costs, the EU's own page on Roam Like at Home.
- Our own prices come from the MegaEsim catalogue, checked 29 September 2026.
