Mobile roaming charges will end within the EU by mid-2017 and will be significantly cut next summer after the European Parliament formally approved the rules.
Mobile phone users will pay the same price to make calls, send text messages and use data wherever they are in the EU from June 15, 2017.
This means users within the EU will be charged the same as they would in their home country.
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 per minute of call made, 0.02 euro per SMS sent, and 0.05 euro per MB of data, excluding VAT.
The new rules aim to prevent consumers receiving huge bills after downloading films or other data while travelling in Europe.
And under 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.
These rules protect the right of every European to access the content of their choice, without interference or discrimination
European Commission vice president Andrus Ansip, responsible for the Digital Single Market, said: “The voice of Europeans has been heard. Today's vote is the final result of intense efforts to put an end to roaming charges in the European Union and to safeguard the open internet.
“As from mid-June 2017, Europeans will pay the same price to use their mobile devices when travelling in the EU as they do at home. And they will already pay less as from April 2016.
“This is not only about money, this is about bringing down barriers in the Digital Single Market. Today's achievement is a first step towards a Telecoms Single Market.”
Commissioner Gunther H Oettinger, in charge of the Digital Economy and Society, said: “Today's agreement shows that the European Union can deliver tangible results to improve the daily life of Europeans.
“Roaming charges will be soon old memories and we will get for the first time ever net neutrality rules in EU law.
“These rules protect the right of every European to access the content of their choice, without interference or discrimination.”
USwitch telecoms spokesman Ernest Doku said: “Today all the toing and froing is finally over, putting the stops on bill shock for those travelling within the EU, when roaming charges are scrapped from June 2017.
“This could be a major win for consumers who have been especially vulnerable to roaming charges since the smartphone market exploded and mobile data consumption soared. Bill shock from holidaying in the EU affects more than nine million UK mobile users a year, according to our research.”
However, Mr Doku said concern remained around if and how mobile operators would recover their costs.
He said: “If this regulation change isn't properly managed, higher mobile phone bills for all may just prove to be the sting in the tail, with infrequent travellers drawing the short straw.
“If price rises do follow, consumers can show their disapproval by moving to another network.”
Conservative MEP Vicky Ford said: “Ending mobile roaming fees from 2017 will be welcomed by millions of people, as they will be able to use their apps, make calls and send a text just as if they were at home.
“We have also ensured important safeguards to prevent excessive usage, and to make sure that phone operators are not forced to offer roaming services at a loss, meaning that domestic customers do not end up subsidising those customers who travel.
“We have achieved a sensible timescale that gives mobile operators the time to sort out the marketplace in preparation for the abolition of roaming fees.”