$384 Cheap Air Canada flights San Francisco (SFO) to London (LHR)

Landing cheap one-way Air Canada flights from SFO to LHR from $384 on Expedia couldn't be easier — just filter by "Price (lowest to highest)." Alternatively, check out our budget-friendly return fares from $517 for your next break.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Start your search for Air Canada flights from SFO to LHR about one month before you want to go. The cheapest time to reserve an international flight is usually 18 to 29 days ahead of your travel date when you can save 17% versus booking four to five months in advance. Regardless of fare class or itinerary, the best day to book international airfare is usually Sunday. Friday is often the most expensive. Travelers booking on a Sunday can save an average of 17% compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Filter your results by "Morning" and "Early Morning" to browse the earliest flights from SFO to LHR. Heading off early means you're 20% less likely to experience cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

Air Canada makes flying from SFO to LHR more comfortable with an excellent in-flight experience and top-tier customer service. You also have the chance to earn points with Air Canada Aeroplan. Be sure to join our free One Key™ rewards program to earn OneKeyCash™*, which can be redeemed on future travel.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.