The route will launch as a six-per-week service before moving to daily flights from winter 2016.
The service from Heathrow Terminal 5 will be operated by a four-class Boeing 777.
Neil Cottrell, British Airways’ head of network planning, said:
“Iran is a large and growing economy and Tehran is a brilliant business city so we are incredibly excited to be adding another gateway to the Middle East for our customers. The recent lifting of sanctions opens up exciting new prospects for Iran as a tourist destination and with its rich heritage, unique architecture and world-class food it’s unsurprising Tehran is tipped to be a popular destination for 2016.”
The airline has a long history of flying to the city and offered the first scheduled flights between London and the Iranian capital in 1946.
Tehran is one of 14 new routes British Airways will be launching this year, which include San Jose, Costa Rica, San Jose, California and Lima in Peru.