Cheap flights from San Francisco to London from $339 SFO → LCY, LGW, LHR, LTN, SEN, STN
San Francisco International Airport (SFO) → London City Airport (LCY), London Gatwick Airport (LGW), London Heathrow Airport (LHR), London Luton Airport (LTN), London Southend Airport (SEN), Stansted Airport (STN)
The cheapest return found recently is $1,053 with Alaska Airlines, 23 Dec – 6 Jan 2027, found yesterday. The cheapest one-way found recently is $339 with Air Canada, 15 Sept 2027, found yesterday.
- Cheapest one-way found recently
- $339, found yesterday
- Cheapest return found recently
- $1,053, 23 Dec to 6 Jan 2027
- Usual return price
- $958 to $1,132
- Cheapest month to fly
- March 2027, return fares from $869 found in the last 7 days
- Airlines with nonstop flights
- British Airways, United Airlines, Virgin Atlantic
Return
The cheapest return fare on each of 3 departure dates is usually $958 to $1,132.
Cheapest return found recently
$1,053
23 Dec – 6 Jan 2027 · Alaska Airlines
San Francisco International Airport (SFO) → London Heathrow Airport (LHR)
Leaves 9:59 p.m. · Return leaves 8:35 a.m. · 77 h 3 min of travel, both ways together
out 2 stops, back 3 stops · via Los Angeles International Airport (LAX), Leonardo da Vinci-Fiumicino Airport (FCO), Venice Marco Polo Airport (VCE), London Heathrow Airport (LHR), O'Hare International Airport (ORD) · separate tickets likely: collect your bags and check in again · overnight connection · 19 h connection
found yesterday
Cheapest nonstop return
$1,039
21 Mar 2027 – 27 Mar 2027 · KLM
San Francisco International Airport (SFO) → London Heathrow Airport (LHR)
Leaves 5:40 p.m. · Return leaves 10:50 p.m. · 21 h 15 min of travel, both ways together
out nonstop, back nonstop
found 4 days ago
Found recently, and the cheapest we hold
$1,053 23 Dec – 6 Jan 2027found yesterdaySee prices for these dates
$869 21 Mar 2027 – 27 Mar 2027found 4 days agoSee prices for these dates
What have prices looked like?
Over 50 days, 24 Sept to 12 Nov, the cheapest return we saw each day was $647 to $869.
At $1,053, the cheapest return found recently is above that range.
Those were the prices on those days, not today's.
Is this a good return price?
Compared with the cheapest return fare on each of 3 departure dates from 23 Nov to 21 Mar 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other 14-night return fares leaving within 3 days of 23 Dec to compare.
Every date we hold
73 fares on 3 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 23 Nov – 29 Nov | $1,216 | United Airlines | San Francisco International Airport (SFO) → London Heathrow Airport (LHR) | out 1 stop, back 4 stops | found 5 days ago | See prices for these dates |
| 23 Dec – 6 Jan 2027 | $1,047 | Frontier Airlines | San Francisco International Airport (SFO) → London Gatwick Airport (LGW) | out 2 stops, back 2 stops | found 4 days ago | See prices for these dates |
| 21 Mar 2027 – 27 Mar 2027 | $869 | Aer Lingus | San Francisco International Airport (SFO) → London Heathrow Airport (LHR) | out 1 stop, back 2 stops | found 4 days ago | See prices for these dates |
Which month looks cheapest?
March 2027 is the cheapest month — from $869.
Airlines on the cheapest dates: United Airlines, Frontier Airlines, Aer Lingus.
One-way
Not enough comparable prices yet for a usual one-way price.
Cheapest one-way found recently
$339
15 Sept 2027 · Air Canada
San Francisco International Airport (SFO) → London Heathrow Airport (LHR)
Leaves 12:15 p.m. · 13 h 45 min trip
1 stop
found yesterday
Cheapest nonstop one-way
None seen yet.
Found recently, and the cheapest we hold
$339 15 Sept 2027found yesterdayOpen this trip
It is also the cheapest one-way we hold, of any age.
What have prices looked like?
Over 31 days, 24 Sept to 12 Nov, the cheapest one-way we saw each day was $243 to $575.
Those were the prices on those days, not today's.
Is this a good one-way price?
Not enough comparable prices yet: we hold one-way fares on 1 departure date and need at least 3 to say what is usual.
Could nearby dates be cheaper?
We hold no other one-way fares leaving within 3 days of 15 Sept 2027 to compare.
Every date we hold
2 fares on 1 departure dates
See every date as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 15 Sept 2027 | $339 | Air Canada | San Francisco International Airport (SFO) → London Heathrow Airport (LHR) | 1 stop | found yesterday | Open this trip |
Airlines on the cheapest dates: Air Canada.
Premium cabin fares from San Francisco to London
We hold no premium economy, business or first-class fares for this route: we collect them for the busiest routes, and this one is not among them yet.
Today's prices for 23 Dec – 6 Jan 2027 in another cabin: Premium economy · Business · First
Today's prices for 15 Sept 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for San Francisco to London?
Return
Fares 7 to 13 days before departure were typically 12% lower than 0 to 6 days before departure.
From the cheapest return each day between 24 Sept and 12 Nov (50 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $852 | $669 | +14% | 9 |
| 7–13 days | $750 | $669 | Cheapest seen | 27 |
| 14–29 days | $750 | $650 | +0% | 30 |
| 30–59 days | $789 | $647 | +5% | 42 |
| 60–89 days | $1,158 | $799 | +54% | 20 |
| 90–179 days | $768 | $726 | +2% | 20 |
| 180+ days | $947 | $808 | +26% | 32 |
One-way
Fares 90 to 179 days before departure were typically 13% lower than 30 to 59 days before departure.
From the cheapest one-way each day between 24 Sept and 12 Nov (31 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 30–59 days | $345 | $243 | +15% | 8 |
| 60–89 days | $548 | $397 | +82% | 11 |
| 90–179 days | $301 | $296 | Cheapest seen | 19 |
| 180+ days | $326 | $326 | +8% | 12 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
San Jose → London
67 km from San Francisco
$1,246
$193 more than flying from San Francisco
23 Dec – 6 Jan 2027 · SJC → LHR · out 1 stop, back 1 stop
found yesterday
Oakland → London
13 km from San Francisco
$3,589
$2,536 more than flying from San Francisco
23 Nov – 29 Nov · OAK → LHR · out 1 stop, back 1 stop
found 5 days ago
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
One-way
San Jose → London
67 km from San Francisco
$344
$5 more than flying from San Francisco
15 Sept 2027 · SJC → LHR · 1 stop
found yesterday
Oakland → London
13 km from San Francisco
$351
$12 more than flying from San Francisco
15 Sept 2027 · OAK → LHR · 1 stop
found yesterday
Cheapest recent price on each route — one way, per traveler in Economy. Distances are in a straight line.
Live price for these dates
The cheapest return found recently is for 23 Dec – 6 Jan 2027. A live search on this page shows what those dates cost now, for one adult in economy.
Questions about this trip
How much is a return flight from San Francisco to London?
The cheapest return found recently is $1,053 with Alaska Airlines, 23 Dec to 6 Jan 2027, found yesterday. The cheapest return we hold, of any age, is $869 with Aer Lingus, 21 Mar 2027 to 27 Mar 2027, found 4 days ago. The cheapest return fare on each of 3 departure dates is usually $958 to $1,132.
How much is a one-way flight from San Francisco to London?
The cheapest one-way found recently is $339 with Air Canada, 15 Sept 2027, found yesterday.
What is the cheapest month to fly from San Francisco to London?
March 2027 is the cheapest month for a return, from $869, 21 Mar 2027 to 27 Mar 2027, found 4 days ago.
How far ahead should I book a flight from San Francisco to London?
In 50 days of prices between 24 Sept and 12 Nov, return fares 7 to 13 days before departure were typically 12% lower than 0 to 6 days before departure. In 31 days of prices between 24 Sept and 12 Nov, one-way fares 90 to 179 days before departure were typically 13% lower than 30 to 59 days before departure.
Is there a direct flight from San Francisco to London?
Yes, the cheapest nonstop return found recently is $1,039 with KLM, 21 Mar 2027 to 27 Mar 2027, found 4 days ago.
How long is the flight from San Francisco to London?
The cheapest one-way found recently, with Air Canada on 15 Sept 2027, takes 13 h 45 min with 1 stop.
Which airlines have the cheapest flights from San Francisco to London?
Between 23 Nov and 21 Mar 2027, United Airlines has the cheapest return on 1 of the 3 departure dates we hold, Frontier Airlines on 1 and Aer Lingus on 1.
Prices are what travelers' searches on Aviasales found in the last 7 days, in US dollars: the price the seller showed on Aviasales; bags may cost extra. Fares change, so check today's price before you book. How our prices work