# How to check in at Athens International Airport (step by step)

> Check-in, security and gate at Athens International Airport (ATH) without stress. Here are the steps and how much time to leave.

Check-in, security and gate at Athens International Airport (ATH) without stress. Here are the steps and how much time to leave.

## Steps

- Check in online 24–48h before your flight
- Arrive at Athens International Airport 2h early (3h for long-haul)
- Clear security: liquids ≤100ml
- Find your gate on the screens or Google
- Keep your boarding pass on your phone — the eSIM keeps you online

## Get online at the airport

Install a MerrSIM eSIM for Greece (from €1.49, 10 GB €8.49) before departure and you’re online the moment you land at Athens International Airport — no WiFi hunt, no roaming.

[MerrSIM — eSIM Greece](https://merrsim.com/destinations/esim-plans-for-greece)

## How an eSIM works

An eSIM is a digital SIM built into your phone: there is no physical card to insert. You buy it online, get a QR code by email and scan it in your settings. Once installed, the profile lives on your phone and activates when you reach Greece, connecting automatically to a local partner network. You can keep your main SIM at the same time, so your number still gets calls and texts while the eSIM handles data.

## Tips to save data

A few small habits make your gigabytes last in Greece. Download Google Maps offline before you head out, set video quality to “Auto” or 480p, and turn off background app refresh. Use hotel WiFi for big updates and high-resolution photo uploads. With these steps, even a modest plan covers the whole trip, and your hotspot stays free for the moments you really need it.

## Does your phone support eSIM?

Before you buy, check two things. First, the phone must be eSIM-compatible: iPhone XR/XS and newer, Samsung Galaxy S20 and newer, Google Pixel 3 and newer, and many recent Motorola, Huawei and Oppo models. Second, it must be carrier-unlocked. You can verify by dialling *#06# — if an EID number appears, your phone supports eSIM. This saves you any surprises when you arrive in Greece.

## eSIM versus roaming

Roaming with your home carrier can be expensive outside bundles — sometimes several euros per gigabyte, with bills that land after the trip. A local eSIM turns that into a fixed price you know up front: you pay in advance, you know exactly how many GB you have, and there are no hidden fees. For a trip to Greece, that means peace of mind and often a real saving compared with leaving roaming switched on unchecked.

## How much data you really need

For normal use — maps, messaging, social media and the odd video — budget about 300–700 MB a day. A light traveller is fine with 3–5 GB for a week, while anyone doing video calls, streaming or laptop hotspot will want 10–20 GB. In Greece, download offline maps and use hotel WiFi for big downloads; that way a 10 GB plan comfortably lasts two weeks. If you run out, you buy a new plan in the app with no waiting.

## FAQ

### How do I get online as soon as I arrive in Greece?
Activate a MerrSIM eSIM for Greece (from €1.49, 10 GB €8.49) by QR before departure; you connect automatically at the airport.


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Author: Etnik Beqiri  
Published: 2026-05-28  
Source: https://merrsim.com/en/blog/check-in-ath-en