If you’re transferring from Heathrow, use the RailAir coach or Tube to Victoria, then train to Gatwick

https://www.mediafire.com/file/wng8cpm7fhpu7wm/pdf-67015-5136.pdf/file

If you’re transferring from Heathrow, use the RailAir coach or Tube to Victoria, then train to Gatwick. Direct coaches also run between airports at certain times—book ahead.