Mobile roaming charges are set to be scrapped within the European Union from June 2017.
Under the new rules, mobile phone users will pay the same price to make calls, send text messages and use data wherever they are in the EU, meaning calling friends or family while travelling will make no difference to bills from June 15, 2017, the European Commission announced.
European negotiators have also reached an agreement on so-called net neutrality rules, which will see internet providers banned from blocking or slowing down access to particular content, services or applications.
Andrus Ansip, the European Commission's vice-president for the Digital Single Market, said: "Europeans have been calling and waiting for the end of roaming charges as well as for net neutrality rules. They have been heard.
"We still have a lot of work ahead of us to create a Digital Single Market. Our plans to make it happen were fully endorsed by heads of state and government last week, and we should move faster than ever on this."
Gunther H Oettinger, commissioner for the Digital Economy and Society, said: "I welcome today's crucial agreement to finally end roaming charges and establish pragmatic net neutrality rules throughout the EU.
"Both are essential for consumers and businesses in today's European digital economy and society.
"We will build on these important foundations in our forthcoming review of the EU's telecoms legislation."
The EC said a series of technical conditions need to be fulfilled in order to abolish roaming charges, but it is "fully committed to implementing those conditions and making sure that the end of roaming charges is operational as of day one".
Roaming charges will become cheaper from April next year, when operators will only be able to charge a small additional amount to domestic prices of up to 0.05 euro (3p) per minute of call made, 0.02 euro (1p) per SMS sent, and 0.05 euro (3p) per MB of data, excluding VAT.
Under the new net neutrality rules, users across the EU will be free to access the content of their choice and will no longer be unfairly blocked or slowed down.
This means access to a start-up's website will not be unfairly slowed down to make way for bigger companies, the EC said.
No service will be hampered because it does not pay an additional fee to internet service providers.
All internet traffic will be treated equally, subject to strict and clearly identified public-interest exceptions such as network security or combating child pornography.
Following today's agreement, the rules will have to be formally approved by the European Parliament and the Council.