The service will be operated with Boeing 787-9 Dreamliner aircraft, which can accommodate up to 298 passengers, and will run until 29 March 2024.
Every day flight AC856 departs London at 11:10 before arriving in Mumbai at 01.35, while flight AC855 will leave Mumbai at 04.25 and land in London at 09.20.
Passengers can choose from Economy, Premium Economy and Air Canada Signature Class, which has exclusive cabins.
The carrier said seats are now available to book via travel agencies.
Stephen Gerrard, Air Canada general manager sales, UK and Ireland, said: “We are delighted to resume our non-stop service between Heathrow and India’s city of dreams, Mumbai.
“Mumbai is one of the top destinations worldwide, renowned for its historical monuments and rich culture.
“Our customers in the United Kingdom will benefit from more travel choice and convenience while travelling for business, leisure or visiting friends and family.”