Cheap Flights from Portland ME to San Francisco International CA from $327

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Flight deals from Portland to San Francisco International

Looking for a cheap last-minute deal or the best round-trip flight from Portland Airport to San Francisco International Airport? If you want to travel next month, round-trip fares start from $510. Find the lowest prices on one-way and round-trip tickets right here.

San Francisco.$327 per passenger.Departing Tue, Aug 18, returning Tue, Aug 25.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Tue, Aug 18, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Tue, Aug 25, arriving in Portland.Price includes taxes and charges.From $327, select.

San Francisco.$368 per passenger.Departing Wed, Oct 14, returning Tue, Oct 20.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Wed, Oct 14, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Tue, Oct 20, arriving in Portland.Price includes taxes and charges.From $368, select.

San Francisco.$390 per passenger.Departing Mon, Sep 14, returning Thu, Sep 17.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Mon, Sep 14, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Thu, Sep 17, arriving in Portland.Price includes taxes and charges.From $390, select.

San Francisco.$403 per passenger.Departing Sun, Aug 23, returning Sat, Sep 5.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Sun, Aug 23, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Sat, Sep 5, arriving in Portland.Price includes taxes and charges.From $403, select.

San Francisco.$408 per passenger.Departing Wed, Jul 22, returning Mon, Aug 3.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Wed, Jul 22, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Mon, Aug 3, arriving in Portland.Price includes taxes and charges.From $408, select.

San Francisco.$409 per passenger.Departing Mon, Jun 29, returning Tue, Jul 7.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Mon, Jun 29, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Tue, Jul 7, arriving in Portland.Price includes taxes and charges.From $409, select.

San Francisco.$428 per passenger.Departing Sat, Feb 13, returning Thu, Feb 18.Round-trip flight with Delta.Outbound indirect flight with Delta, departing from Portland on Sat, Feb 13, arriving in San Francisco International.Inbound indirect flight with Delta, departing from San Francisco International on Thu, Feb 18, arriving in Portland.Price includes taxes and charges.From $428, select.

San Francisco.$454 per passenger.Departing Sat, Jul 4, returning Sat, Jul 11.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Sat, Jul 4, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Sat, Jul 11, arriving in Portland.Price includes taxes and charges.From $454, select.

San Francisco.$507 per passenger.Departing Sat, May 30, returning Wed, Jun 3.Round-trip flight with United.Outbound indirect flight with United, departing from Portland on Sat, May 30, arriving in San Francisco International.Inbound indirect flight with United, departing from San Francisco International on Wed, Jun 3, arriving in Portland.Price includes taxes and charges.From $507, select.

San Francisco.$510 per passenger.Departing Thu, Jun 11, returning Wed, Jun 17.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Thu, Jun 11, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Wed, Jun 17, arriving in Portland.Price includes taxes and charges.From $510, select.

San Francisco.$645 per passenger.Departing Tue, May 19, returning Tue, May 26.Round-trip flight with Delta.Outbound indirect flight with Delta, departing from Portland on Tue, May 19, arriving in San Francisco International.Inbound indirect flight with Delta, departing from San Francisco International on Tue, May 26, arriving in Portland.Price includes taxes and charges.From $645, select.

San Francisco.$716 per passenger.Departing Mon, Nov 23, returning Sun, Nov 29.Round-trip flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departing from Portland on Mon, Nov 23, arriving in San Francisco International.Inbound indirect flight with Southwest Airlines, departing from San Francisco International on Sun, Nov 29, arriving in Portland.Price includes taxes and charges.From $716, select.

Find the cheapest month to fly from Portland to San Francisco International

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Portland to San Francisco International flights are currently cheapest in August.

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Direct flights from Portland to San Francisco International

Portland to San Francisco International: Alternative routes

Compare routes from Portland to San Francisco below. You may find an airport to fly into that's cheaper, faster, or easier than San Francisco International.

Portland to San Francisco: Flight information

The things to know before you go.

Cheapest flight found	$327
Cheapest month to fly	August
Average flight time	6 hrs, 35 mins
Most popular airline	United
Average flights per week	1

Finding cheap flights from Portland to San Francisco International: Frequently asked questions

How much are round-trip flights from Portland to San Francisco International?

The best price we found for a round-trip flight from Portland to San Francisco International is $327. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.

How long does it take to fly from Portland to San Francisco International?

6 hours and 35 minutes is the average flight time from Portland to San Francisco International.

Which airlines fly direct from Portland to San Francisco International?

United flies direct from Portland to San Francisco International.

How many flights are there a week from Portland to San Francisco International?

There is one flight per week flying from Portland to San Francisco International, as of May 2026.

When is the cheapest time to fly from Portland to San Francisco International?

The cheapest month to fly from Portland to San Francisco International is usually August.

Which upcoming date is cheapest to fly from Portland Airport to San Francisco International Airport on?

After crunching the numbers on our flight calendar, we found that it's currently cheapest to fly from Portland Airport to San Francisco International Airport on Tuesday, August 18, 2026.

Can I get a direct flight from Portland Airport to San Francisco International Airport?

Yes – the average flight time is 6 hours and 35 minutes.

How can I find the best flight deal to San Francisco International?

We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to San Francisco International but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.

When is the best time to book flights to San Francisco?

We crunched all the numbers in our flight calendar, and it looks like the cheapest time to book a flight to San Francisco is around 40 days in advance, so don’t leave your flight to the last minute.

Which is the cheapest airline to fly with from Portland Airport to San Francisco International?

Currently, Southwest Airlines offers the cheapest flight tickets to San Francisco International.

Flying from Portland International Jetport Airport (PWM) to San Francisco International Airport (SFO): what you need to know

San Francisco is three hours behind Portland and is in the UTC-7 timezone.
Get to the airport on time so you don't miss your PWM to SFO flight. Be there at least two hours ahead for international flights and an hour early for domestic departures to avoid sprinting to your gate.
Be prepared for bigger queues during popular months such as August. Arriving up to four hours ahead of an international flight and two hours for domestic departures will help ensure a smooth travel experience.
If you'd like to add a stop to your trip, just uncheck 'Direct flights only' when searching for your ticket from Portland International Jetport Airport to San Francisco International Airport. These are the top stopovers between PWM and SFO:
- Detroit Metropolitan Wayne County Airport
- Newark Liberty International Airport
- O'Hare International Airport

How to find the cheapest flights from Portland International Jetport Airport (PWM) to San Francisco International Airport (SFO)

$182 is the best price for a one-way Portland International Jetport Airport to San Francisco International Airport flight. Return flights start at $327. These fares can change based on demand and availability.
It's often best to book in advance if you want to find cheap tickets from PWM to SFO. That's because airlines adjust prices based on demand, which tends to increase closer to departure.
Finding cheap flights from Portland International Jetport Airport to San Francisco International Airport is easy if you're flexible with your travel plans. Use the 'Whole month' function to see the best prices across every month and snap up a great deal.
There's no need to check every day to find out if fares have gone down when you create a Price Alert. We'll notify you the moment a special offer becomes available on cheap flights from PWM to SFO.
Select your preferred arrival and departure times, airlines and number of stops with the filters. Or sort your results by 'Cheapest' to find the best deals on flights from Portland International Jetport Airport to San Francisco International Airport.

Handy information about Portland International Jetport Airport (PWM)

PWM's address is 1001 Westbrook Street.
Portland International Jetport Airport maintains a strong on-time record, so flight disruptions are less likely. Departures from PWM land at their destination as scheduled 82.15% of the time.
Central Portland to Portland International Jetport Airport is approximately 8 kilometers. Depending on traffic, it'll take about 15 minutes to get there if you're ride-sharing, catching a cab or driving.
Expect a journey time of roughly 40 minutes when using public transport.
Get your trip off to a relaxed start by staying near PWM. Whether you're taking an early flight from Portland International Jetport Airport to San Francisco International Airport or just don't want to be rushed, these hotels have you covered:

Arriving at San Francisco International Airport (SFO)

Consider staying in a hotel near SFO if you're on a late Portland International Jetport Airport to San Francisco International Airport flight. Pick one of these options and skip the long transfer after landing:
Travel at your own speed with a San Francisco International Airport rental car. Pick up your wheels from Dollar, Thrifty or Hertz and discover more of San Francisco and beyond.
Lock in the lowest price by reserving your ride from San Francisco International Airport around one week before your departure date.

Getting from San Francisco International Airport (SFO) to central San Francisco

From San Francisco International Airport, San Francisco is approximately 21 kilometers away. It takes around 20 minutes to reach the center by car.
Getting to the center by public transport takes roughly 45 minutes.

When to fly to San Francisco International Airport (SFO)

The quietest month for a flight from Portland International Jetport Airport to San Francisco International Airport is February, while August is the busiest. Pick the best time to go to San Francisco based on whether you prefer a faster pace or a more relaxed vibe.
The warmest month in San Francisco is September, with the temperature ranging between 12ºC (54ºF) and 22ºC (72ºF). Book your flights from Portland International Jetport Airport to San Francisco International Airport in this month if this is the type of weather you like.
January has average temperatures of between 6ºC (43ºF) and 16ºC (61ºF). Look for cheap tickets from PWM to SFO sometime then if you want to travel in cooler conditions.

Explore more of United States

San Francisco has loads to offer, but there are so many other parts of United States you should also see. About 64 kilometers south-east of San Francisco, a trip to San Jose will keep you on the go. Don't miss top attractions like Winchester Mystery House, Rosicrucian Egyptian Museum and San Jose Museum of Art.
Fresno is another well-known destination in United States and is around 257 kilometers south-east of San Francisco. No trip is complete without experiencing Forestiere Underground Gardens, Fresno Chaffee Zoo and Shinzen Japanese Garden.