Mobile phone use in Bulgaria 

Please consider the following information, as having access to a phone line or VoIP service can make it much easier to contact the organisers should you require assistance. 

EU travellers

If you are travelling to Bulgaria from another EU country, your mobile phone will work as normal under EU “Roam Like at Home” rules. Voice calls and SMS require no special settings. To use mobile internet, please make sure that Data Roaming is switched on in your phone settings. You should not incur additional charges beyond your usual tariff for normal use during a short stay.

Travellers from the UK

Since the UK is no longer part of the EU roaming framework, UK mobile users may incur roaming charges in Bulgaria. Some UK mobile operators (e.g. SMARTY and giffgaff) offer plans that include calls, texts, and mobile data roaming in Bulgaria, subject to fair-use limits and data caps, while most other UK networks offer international roaming add-ons or daily passes that can be enabled before travel. To use mobile internet, ensure that Data Roaming is switched on. Travellers are advised to check roaming rates, allowances, and available bundles with their mobile provider before departure.

Travellers from other countries 

You may wish to consider purchasing a dedicated travel plan or eSIM. While we do not endorse any particular provider, some participants at CA2HL in 2025 reported successful use of an eSIM purchased from eSIM.sm. Please make sure that Data Roaming is switched on in your phone settings. If you are using an eSIM or secondary SIM for data, ensure that data roaming is disabled on your main SIM to avoid unintended charges.

Internet

The locations that participants will attend are not educational establishments, and do not offer eduroam access. The House of Culture, and the Trimontium Hotel will have their own WiFi networks -- you will receive the passwords as part of your registration process on arrival.