Heathrow has been named as the preferred site for expansion in the south east.
The Airports Commission has today published the long-awaited report choosing a third runway at Heathrow, but only if it meets stringent conditions on air quality, noise pollution and carbon emissions.
The Commission said that a second runway at Gatwick was a "credible" option but was less able to provide connections to long-haul destinations and would create lower levels of economic growth.
A third option for extending the runways at Heathrow was rejected.
The report said measures to reduce noise and environmental effects will include a ban on night flights and a noise levy to fund a "far stronger and more generous set of compensation and mitigation schemes".
The report also suggests expansion at Heathrow could create 70,000 new jobs and result in airlines flying to 40 new flight destinations by 2050.
"The best answer is to expand Heathrow's capacity through a new north-west runway," the Commission chairman Howard Davies said.
"Heathrow is best placed to provide the type of capacity which is most urgently required: long haul destinations to new markets.
"It provides the greatest benefits for business passengers and the broader economy.
"Adding capacity at Heathrow also provides an opportunity to change the airport's relationship with its local communities."
The government has said it will take time to study the report before making a final decision which is likely to be delayed until after the Mayoral election next May.