Save money by using contactless or Oyster on the tube and Elizabeth line; fares cap daily
https://www.scribd.com/document/1074920514/Getting-to-Heathrow-from-Gatwick-Easiest-Inter-Airport-Transfers-178501
Save money by using contactless or Oyster on the tube and Elizabeth line; fares cap daily, and you won’t need to queue for paper tickets at stations.