Starting from May 15th 2019 the EU law states a standardized calling / roaming rate of maximum 23 cent/min for mobile phone calls made within the EU. Meaning that from now on it does no longer matter where you are in the EU and where you have made your contract, CALLING FROM ONE EU COUNTRY TO ANOTHER EU COUNTRY COST 23 CENT/MIN. Short text messages (SMS) only cost 7 cent/message.
That is very good news and one step forward to a EU wide flat rate system, by adding value to the existing EU roaming system in which you can call the country you are visiting at the moment and make calls to the country you made the contract for local rates (home country rates) or for free in case you have a flat rate contract.
The new EU roaming rates apply for new contracts made after May 15th 2019.
Existing contracts have to be adjusted to these rates by the provider automatically latest until 15th of July 2019. In case you want to benefit from the new rates earlier immediately, you need to contact your provider directly to perform that change manually.