How will the Free EU Roaming plan benefit travellers?

From 15th June 2017, data roaming for UK customers across the European Union will be free.
The new plan will enable mobile phone users to maximise potential from their normal data, text and call packages across dozens of destinations in Europe, without having to pay any additional charges.
Let's take a look at some frequently asked questions:
Do I need to opt in?
Several mobile service providers across the UK have already abandoned roaming charges over the last few months, but from June 15th 2017 all remaining phone companies who haven’t opted out, will be offering this. Customers do not have to opt in, as this will be done automatically, though some Android users are being advised to check settings to ensure outgoing international is not barred.
Typically, service providers are confirming via text message when this new change is going live.
Will I have to pay extra to send/recieve a call in EU?
All phone calls in participating countries will be taken from your usual monthly allowance and you will not be charged any extra. This also includes sending and receiving text messages and voicemails.
Which countries does this apply to?
The new changes will come into effect for all leading service providers, however the countries where free roaming is offered may vary slightly.
Free roaming will be typically be available in the following countries: Austria, Azores, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Canary Islands, Denmark, Estonia, Finland, France, French Guyana, Germany, Gibraltar, Greece, Guadeloupe, Guernsey, Hungary, Iceland, Ireland, Isle of Man, Italy, Jersey, Latvia, Liechtenstein, Lithuania, Luxembourg, Madeira, Malta, Martinique, Mayotte, Monaco, Netherlands, Norway, Poland, Portugal, Reunion Islands, Romania, San Marino, Saint Martin (French), Saint Barthelemy, Slovakia, Slovenia, Spain, Sweden and Vatican City (Italy).
Are there any differnces across individual networks?
Yes, aside from the core inclusions, extra destinations will vary based on your network provider.
● O2 will cover 47 different countries for those on contracts, including: Belgium, Denmark, France, Germany, Greece, Ireland, Italy, Norway, Poland, Portugal, Romania, Spain, Sweden and The Netherlands. For pay as you go customers, Guernsey, Isle of Man, Jersey, Monaco and Switzerland are not included. Learn more about O2 roaming.
● EE will be extending their data roaming to Iceland, Norway, Liechtenstein, Switzerland, Monaco, Isle of Man, Jersey and Guernsey. Those on pay as you go will be able to use the first 15GB of their data allowance in the EU. Learn more about EE roaming.
● Vodafone will be offering free roaming in 40 of the countries, but has also added Turkey to their list. Those visiting Serbia and Montenegro will still have to pay for roaming. Learn more about Vodafone roaming.
Find your perfect holiday smartphone at Mobiles.co.uk, and happy travelling.