The aircraft left the London airport just before 10am with a return service set to depart the Scottish terminal this afternoon.
It will form part of a new year-round service.
A ceremony is due to be held upon the aircraft touching down in Inverness to commemorate the return of the service, since BA terminated it in 1997.
Inverness did previously possess a link with London City Airport but provider Flybe suspended the service in February 2015 citing a shortage of passengers.
Low-cost carrier Easyjet provides an alternative service to London through its services to Gatwick and Luton.
A spokesperson for Heathrow said the new addition would give the region a “huge boost”, he said: "We’re delighted that Inverness will now get all of the benefits that connecting to the UK’s only hub provides.
"When the city lost its hub connection, the north of Scotland saw its global connectivity severely reduced and the region has been fighting to re-establish it ever since.
"Heathrow is one of only six airports in the world with over 50 long-haul destinations - reconnecting to Heathrow will give a huge boost to
Inverness and the north of Scotland, opening up lucrative trade routes and driving the inbound tourism and foreign investment that will create local jobs."
