Plymouth no longer has its own airport, the nearest is Exeter however Bristol and London are other options.
There is a new direct coach service from Bristol Airport to Plymouth costing just £25 return, coaches leave the airport once an hour through the day and less frequently through the night. The Falcon coaches are equipped with Air Conditioning, Wifi and charging sockets. Advanced booking of a specific time and day costs as little as £1.50. Click for full details of the coach service.
London Heathrow has a frequent train service to London Paddington station, where there is a direct train service to Plymouth.