Airfares for flights from Heathrow are currently £95 higher due to the lack of capacity at the UK’s hub airport, according to a new report.
Research firm Frontier Economics also estimated that the average ticket price could be £300 lower by 2030 if Heathrow was allowed to expand, while a third runway could add 40 new routes from the airport.
The report, commissioned by the airport, found that airfares have been pushed up by around £95 because Heathrow is already operating at full capacity.
Frontier said that the figures included the costs of building a new runway and the savings that passengers will benefit from due to the extra capacity the extra runway will create.
Heathrow chief executive Colin Matthews said that not building a third runway would be a “disincentive to doing business in the UK”.
“The private sector stands ready to invest in the infrastructure Britain needs,” added Matthews.
“Government has it within its power to lower prices for consumers by taking a clear decision to support expansion and end the years of prevarication that are now causing fares to rise and routes to be constrained.”
The Airports Commission, headed by former CBI boss Sir Howard Davies, is currently looking at two possible expansion options at Heathrow, as well as a possible second runway at Gatwick.
The proposal for a new airport in the Thames estuary, dubbed Boris Island after London mayor Boris Johnson, is also still being considered and could be added to the shortlist if it is shown to be economically viable.
The commission will make its final recommendation in summer 2015 after the next general election.
Frontier argued that passengers would benefit more if both Heathrow and Gatwick were allowed to expand.
The research firm added that Heathrow could add long-haul routes to key cities in emerging markets such as Kolkata in India, Mombasa in Kenya and the Peruvian capital Lima.
Expansion would also improve connections between Heathrow and UK regional airports such as Inverness, Liverpool, Newquay and Humberside.
Frontier said that adding a second runway at Gatwick would add between five and seven new routes, which would be mainly to package holiday destinations.