The Department for Transport released a draft policy backing a third runway at Heathrow and a new terminal, but its own impact analysis estimates the project would lift UK GDP by only 0.05 %, far below the airport’s claim of 0.5 %. The discrepancy fuels a fresh round of debate over the £33 bn scheme’s viability and its alleged benefits for the broader economy.

Heathrow argues the analysis is narrow, saying it ignores a projected 50 % rise in cargo capacity—worth roughly £300 bn of UK goods trade—and potential new carriers such as easyJet that could boost passenger numbers. Trade unions GMB and Community back the plan, citing tens of thousands of jobs and training opportunities during construction and operation. Heathrow says capacity limits curb growth, Emirates chief Tim Clark agrees.

The DfT puts the runway’s overall benefit at just over £40 bn, translating to the modest 0.05 % GDP lift, while critics like the New Economics Foundation warn that social and climate costs outweigh any gain. With political uncertainty mounting—Chancellor Rachel Reeves revived the scheme, but newly elected MP Andy Burnham questions its national relevance—the project faces an uphill battle.