The daily service between the two airports resumed on Tuesday (3 May) after BA ended the service in 1997.
The move has been hailed as a boost to the area's economy and tourism industry.
BA sales manager Keith Chuter said: "We appreciate that the local business community has lobbied long and hard for British Airways to resume services to Inverness as an important element in boosting the economy of the city and the region as a whole
"The arrival this morning of BA1468 from Heathrow marks an important day for everyone involved.
"I know that the business community and the people in the region are delighted that British Airways has returned to Inverness. So are we."
The new route has been welcomed by the national tourism body and by the business community in Inverness and the surrounding area.
Malcolm Roughead, chief executive at VisitScotland, said: "This new route tees up a fantastic opportunity for visitors from London and the South East - an important target market - to fly directly into the heart of the Highlands where they can explore the stunning landscapes of the North Coast 500, test their swing at one of the many world-class golf courses, such as Scottish Open hosts, Castle Stuart, and sample the spirit of Scotland on a whisky trail."