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Cheap flights from Portsmouth to Riverside from £421

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 27/9. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — LAX
20 Jul — 27 Jul1
1 adult

Cheap flight deals from Portsmouth to Riverside

Keep the following information in mind while searching for Portsmouth to Riverside flight deals. Data was last updated 15 July 2025.

Round-trip from

£542

One-way from

£421

Popular in

August

Cheapest in

March

Average price

£777
KLM
  • KLM
  • 27/8-3/9
  • 2 total stops
  • 48h 25m total
  • Portsmouth to Riverside
Aer Lingus
  • Aer Lingus
  • 27/9
  • 1 total stop
  • 16h 45m total
  • Portsmouth to Riverside
Highest demand for flights based on searches. 17% potential increase in price (£116 potential increase over avg. return price).
Cheapest flight prices on average. 4% potential price decrease (£24 potential savings vs. average return price).
Average for round-trip flights in July 2025

Find flight deals from Portsmouth to Riverside

Cheapest flights from Portsmouth to Riverside
Explore the most affordable flight options available from Portsmouth to Riverside. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 15 July 2025.

Wed 27/809:20SOU - LAX
1 stop13h 30mKLM
Wed 3/913:50LAX - SOU
1 stop34h 55mKLM
Deal found 13/7£542
Wed 13/809:20SOU - LAX
2 stops19h 02mDelta
Wed 20/811:50LAX - SOU
2 stops22h 00mDelta
Deal found 14/7£582
Wed 27/817:35SOU - LAX
3 stops31h 30mMultiple Airlines
Wed 3/921:25LAX - SOU
2 stops27h 20mMultiple Airlines
Deal found 13/7£630
Wed 13/809:10SOU - LAX
1 stop17h 15mAer Lingus
Wed 20/820:15LAX - SOU
1 stop15h 15mAer Lingus
Deal found 14/7£743
Sat 6/909:40SOU - LAX
1 stop16h 45mBritish Airways
Sun 21/920:15LAX - SOU
1 stop15h 15mBritish Airways
Deal found 14/7£759

Cheapflights Fare Finder

Customise your flight search to find flights from Portsmouth to Riverside that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 15 July 2025.
Use the filters below to find and compare flights from Portsmouth to Riverside that are best for you.

Fly from

Portsmouth

Fly to

Riverside

Route

Depart

Return

Price

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Wed 27/8

09:20-14:50

1 stop13h 30m

Los Angeles

Wed 3/9

13:50-08:45

1 stop34h 55m

£542

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Wed 13/8

09:20-20:22

2 stops19h 02m

Los Angeles

Wed 20/8

11:50-17:50

2 stops22h 00m

£582

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Wed 27/8

17:35-17:05

3 stops31h 30m

Los Angeles

Wed 3/9

21:25-08:45

2 stops27h 20m

£630

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Wed 13/8

09:10-18:25

1 stop17h 15m

Los Angeles

Wed 20/8

20:15-19:30

1 stop15h 15m

£743

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Sat 6/9

09:40-18:25

1 stop16h 45m

Los Angeles

Sun 21/9

20:15-19:30

1 stop15h 15m

£759

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Sat 27/9

09:40-18:25

1 stop16h 45m

£421

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Sat 27/9

08:00-08:42

3 stops32h 42m

£508

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Mon 4/8

18:25-11:50

1 stop25h 25m

£1,208

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Thu 9/10

09:40-18:25

1 stop16h 45m

£1,365

SouthamptonLos Angeles

SOU - LAX

SOULAX

Southampton Eastleigh

Sun 27/7

17:35-14:50

1 stop29h 15m

£1,485

Flights are sorted by cheapest return flights first.

Deals found on 13/7

Best time to book a flight from Portsmouth to Riverside

Have a flexible travel schedule? Discover the best time to fly to Riverside from Portsmouth with our price prediction graph.
Estimated return price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Portsmouth to Riverside

What is the cheapest month to book a flight from Portsmouth to Riverside?

Currently, January is the cheapest month in which you can book a flight from Portsmouth to Riverside (average of £575). Flying from Portsmouth to Riverside in July is currently the most expensive (average of £811). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from P0R to R1V?

Find hourly flight availability from Portsmouth to Riverside. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 15 July 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Portsmouth to Riverside as you normally would.

What is the cheapest day to fly from Portsmouth to Riverside?

Use this chart to determine the cheapest time to fly return from Portsmouth to Riverside. Price data was last updated on 29 September 2024.

Travellers seeking maximum savings on their Portsmouth to Riverside flight should consider departing on Tuesday mornings when fares are most often at their lowest. Monday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Portsmouth to Riverside

Explore weekly flight availability from Portsmouth to Riverside. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 15 July 2025.

The most flights from P0R to R1V are scheduled on a Saturday (57 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (56 on average).

Reviews of airlines servicing Riverside

Get insights into the airlines that provide service to Riverside. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Riverside. Reviews last updated 15 July 2025.
Check out reviews from past customers who have flown with Delta, KLM, andAer Lingus from Portsmouth to Riverside to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
8.0
Very Good

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Boarding

8.2

Crew

8.5

Food

7.3

Entertainment

7.9

Comfort

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

Find useful and relevant information for your journey from Portsmouth to Riverside. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What are the cheapest airlines to fly from Portsmouth to Riverside one-way?

    The cheapet airlines for a one-way flight from Portsmouth to Riverside are Aer Lingus (£421), Delta (£1,208), and British Airways (£1,365).

  • What are the most reliable airlines from Portsmouth to Riverside?

    The top 3 most reliable airlines when flying from Portsmouth to Riverside are SriLankan Airlines (94%), KLM (88%) and Air France (88%).

  • What are the cheapest flights from Portsmouth to Riverside?

    While on average a flight from Portsmouth to Riverside is generally £2,056, our data shows the cheapest flight currently is £385. When looking at the most popular route, (Southampton Eastleigh - Los Angeles), you can expect to pay £582 for that flight.

  • Can I find deals for flights from Portsmouth to Riverside that include hotel bookings?

    Yes. In addition to deals on Portsmouth to Riverside flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Portsmouth to Riverside?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portsmouth to Riverside.

  • Can I find deals for business class flights from Portsmouth to Riverside?

    Yes. Cheapflights offers flight deals from Portsmouth to Riverside by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Portsmouth to Riverside?

    Currently, January is the cheapest month in which you can book a flight from Portsmouth to Riverside (average of £575). Flying from Portsmouth to Riverside in July is currently the most expensive (average of £811). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Portsmouth to Riverside

See prices for flight routes from nearby airports that may be better suited for you.

Top 10 airlines flying from Portsmouth to Riverside

Discover the top 10 airlines that operate flights from Portsmouth to Riverside. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 15 July 2025.
AirlineCheapestAverageFlexibilityOn-time
SWISSCheapest£276Average£552FlexibilityNo cancel feeOn-time79%
Search SWISS flights
FinnairCheapest£279Average£469FlexibilityNo cancel feeOn-time76%
Search Finnair flights
Norse Atlantic UKCheapest£303Average£514FlexibilityNo cancel feeOn-timeN/A
Search Norse Atlantic UK flights
DeltaCheapest£327Average£559FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
KLMCheapest£345Average£509FlexibilityNo cancel feeOn-time75%
Search KLM flights
Air FranceCheapest£353Average£458FlexibilityNo cancel feeOn-time77%
Search Air France flights
Brussels AirlinesCheapest£353Average£475FlexibilityNo cancel feeOn-timeN/A
Search Brussels Airlines flights
Scandinavian AirlinesCheapest£354Average£500FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
United AirlinesCheapest£357Average£538FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Austrian AirlinesCheapest£358Average£473FlexibilityNo cancel feeOn-time78%
Search Austrian Airlines flights

Fly with Cheapflights

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How does Cheapflights help users find flights from Portsmouth to Riverside?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Portsmouth to Riverside. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from Portsmouth to Riverside?

Cheapflights helps you find that perfect flight to Riverside from Portsmouth by searching from hundreds of airlines and agencies you know and love. We are also free to use, in case you were wondering!

Can Cheapflights find flights from Portsmouth to Riverside with no change fees?

Yes, we can. To see specific flights from Portsmouth to Riverside with no change fees, users can toggle flexible booking options after using the search form above to find flights.

Can Cheapflights notify me if prices for flights from Portsmouth to Riverside become cheaper?

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Riverside from Portsmouth today and book when prices fit your budget.

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