Hillingdon Hopsital will not go ahead with a "much-needed" temporary car park due to costs.
The hospital's NHS Foundation Trust secured temporary planning permission to build a single-deck car park on its Pield Heath Road site in December 2014.
The development would have created an extra 89 spaces for the next five years, adding to the existing car park's 390 spots.
But a spokesman for the trust said it was not an economically viable project in its present form.
He added: “Following the detailed design to meet the planning requirements and a competitive tender process, the costs to build the car park deck are now significantly greater than originally envisaged."
The car park was needed to help alleviate problems caused by vehicles queuing on Pield Heath Road.
The spokesman added: “The trust continues to recognise that parking capacity does not adequately meet the levels of demand being experienced and will continue to consider options to improve parking capacity at the Hillingdon Hospital site, as a matter of urgency."
The hospital said it was unable to release the figures of how much the car park would cost.
Speaking to getwestlondon last year, Steve Watkins, a spokesman for the Hillingdon Hospitals NHS Foundation Trust, which runs the hospital, said: "Adequate parking facilities are a challenge for most hospitals and Hillingdon is no exception.
"The hospital is well-served by public transport but a lot of patients still arrive by car and have to queue for entry during peak hours.”
