As of 15 June, Europeans will be able to travel in the EU without roaming charges, after representatives of the European Parliament, the Council and the Commission agreed on how to regulate wholesale roaming markets.
EU negotiators agreed on the following wholesale caps:

- 3.2 cents per minute of voice call, as of 15 June 2017

- 1 cent per SMS, as of 15 June 2017

- A step by step reduction over 5 years for data caps decreasing from €7.7 per GB (as of 15 June 2017) to €6 per GB (as of 1 January 2018), €4.5 per GB (as of 1 January 2019), €3.5 per GB (as of 1 January 2020), €3 per GB (as of 1 January 2021) and €2.5 per GB (as of 1 January 2022).

Read the press release and a summary by Euractiv.com. Detials in Czech are available here.

Look also at figures on private travel destinations of Czechs in 2015. In 2015, the greatest number of Czechs travelled to Slovakia, Austria and Germany (short routes) and Slovakia, Croatia and Italy (longer routes).