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$79+ Cheap flights from Santa Rosa to Ontario (STS - ONT)

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 3/31. Fares are subject to change and may not be available on all flights or dates of travel.
STS — ONT
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
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Cheap flight deals from Santa Rosa to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Santa Rosa (STS) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated October 30, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$135
(SmartFares)

One-way from

$79
(Alaska Airlines)

Popular in

June

Cheapest in

December

Average price

$82
Provider with most accurate pricing for Santa Rosa Sonoma County-Ontario flight deals.
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Provider most trusted by Cheapflights users for Santa Rosa Sonoma County-Ontario flights.
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From Santa Rosa Sonoma County to Ontario
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One-way flight from Santa Rosa Sonoma County to Ontario
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Highest demand for flights based on searches. 23% potential increase in price ($68 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($8 potential savings vs. average RT price).
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Average for round-trip flights in October 2025
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Find flight deals from Santa Rosa to Ontario

Cheapest flights from Santa Rosa to Ontario
Explore the most affordable flight options available from Santa Rosa to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 30, 2025.

This American Airlines deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/44:26 pmSTS - ONT
1 stop5h 34mAmerican Airlines
Mon 12/89:59 amONT - STS
1 stop5h 57mAmerican Airlines
Deal found 10/30$277
This Alaska Airlines deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/227:00 pmSTS - ONT
1 stop4h 55mAlaska Airlines
Wed 12/37:10 amONT - STS
1 stop12h 05mAlaska Airlines
Deal found 10/30$302
This Alaska Airlines deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/56:54 pmSTS - ONT
1 stop25h 09mAlaska Airlines
Sun 12/77:10 amONT - STS
1 stop25h 38mAlaska Airlines
Deal found 10/29$312
This Alaska Airlines deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/46:54 pmSTS - ONT
1 stop25h 09mAlaska Airlines
Sun 12/77:10 amONT - STS
1 stop25h 38mAlaska Airlines
Deal found 10/29$322
This lastminute.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure lastminute.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/42:21 pmSTS - ONT
1 stop9h 08mHawaiian Airlines
Mon 12/86:00 amONT - STS
1 stop7h 29mHawaiian Airlines
Deal found 10/29$328
This Alaska Airlines deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/202:22 pmSTS - ONT
1 stop9h 10mAlaska Airlines
Wed 12/37:10 amONT - STS
1 stop12h 05mAlaska Airlines
Deal found 10/30$332
This Cheapflightsfares deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/47:50 amSTS - ONT
1 stop4h 56mAlaska Airlines
Sat 12/61:26 pmONT - STS
1 stop5h 49mAlaska Airlines
Deal found 10/30$339
This Alaska Airlines deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/202:22 pmSTS - ONT
1 stop9h 10mAlaska Airlines
Tue 12/27:10 amONT - STS
1 stop25h 38mAlaska Airlines
Deal found 10/30$362
This Alaska Airlines deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/272:41 pmSTS - ONT
1 stop19h 14mAlaska Airlines
Sat 12/67:10 amONT - STS
1 stop25h 38mAlaska Airlines
Deal found 10/30$363
This Alaska Airlines deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/272:41 pmSTS - ONT
1 stop19h 14mAlaska Airlines
Sun 12/77:10 amONT - STS
1 stop25h 38mAlaska Airlines
Deal found 10/30$373

Cheapflights Fare Finder

 
Customize your flight search to find flights from Santa Rosa to Ontario 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 2,558,603 searches. Data last updated October 30, 2025.
Use the filters below to find and compare flights from Santa Rosa to Ontario that are best for you.

Fly from

Santa Rosa

Fly to

Ontario

Route

Depart

Return

Price

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Thu 4/9

3:45 pm-5:12 pm

Nonstop1h 27m

Ontario

Mon 4/13

1:30 pm-3:01 pm

Nonstop1h 31m

$135

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Tue 2/3

7:50 am-1:06 pm

1 stop5h 16m

Ontario

Sat 2/7

1:46 pm-7:24 pm

1 stop5h 38m

$299

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Wed 12/10

7:50 am-8:03 pm

1 stop12h 13m

Ontario

Sat 12/13

7:10 am-7:15 pm

1 stop12h 05m

$302

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Sat 11/22

7:00 pm-11:55 pm

1 stop4h 55m

Ontario

Wed 12/3

7:10 am-7:15 pm

1 stop12h 05m

$302

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Fri 2/13

7:00 pm-7:47 pm

1 stop24h 47m

Ontario

Sun 2/22

7:00 am-12:08 pm

1 stop5h 08m

$312

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Fri 2/13

7:00 pm-4:53 pm

1 stop21h 53m

Ontario

Mon 2/23

6:00 pm-7:07 pm

1 stop25h 07m

$312

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Fri 2/20

11:55 am-4:53 pm

1 stop4h 58m

Ontario

Sat 2/28

7:00 am-12:08 pm

1 stop5h 08m

$312

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Fri 12/12

6:54 pm-8:03 pm

1 stop25h 09m

Ontario

Sun 12/14

7:10 am-8:48 am

1 stop25h 38m

$312

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Fri 1/16

6:30 pm-1:06 pm

1 stop18h 36m

Ontario

Sun 1/18

1:46 pm-7:24 pm

1 stop5h 38m

$312

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

Thu 4/9

6:00 am-12:55 pm

2 stops6h 55m

Ontario

Mon 4/13

3:35 pm-10:40 pm

2 stops7h 05m

$318

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/30

Showing 1-10 of 20 results
1
2

Compare providers for flights from Santa Rosa to Ontario

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Santa Rosa to Ontario in October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Santa Rosa-Ontario flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Santa Rosa-Ontario flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Santa Rosa-Ontario flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Santa Rosa-Ontario flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Santa Rosa-Ontario flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Santa Rosa to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Santa Rosa with our price prediction graph.
Estimated round-trip 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 Santa Rosa to Ontario

What is the cheapest month to book a flight from Santa Rosa to Ontario?

Currently, February is the cheapest month in which you can book a flight from Santa Rosa to Ontario (average of $19). Flying from Santa Rosa to Ontario in July is currently the most expensive (average of $57). 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 STS to ONT?

Find hourly flight availability from Santa Rosa to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 30, 2025.

One of the essential ways to save on airfare from Santa Rosa to Ontario is to remain as flexible as possible. Flights that are in the afternoon tend to be the most expensive. A flight in the morning could potentially save you up to 72% on airfare.

How much does it cost to fly round-trip from Santa Rosa to Ontario?

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated October 30, 2025.
Read reviews from past customers who have flown Alaska Airlines, Avelo Airlines, and American Airlines from Santa Rosa to Ontario. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
11,219 reviews

Comfort

7.8

Boarding

8.1

Food

7.1

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Alaska Airlines
8.0
Very good
11,219 reviews
Alaska Airlines
8.0
Very good
11,219 reviews

Comfort

7.8

Boarding

8.1

Food

7.1

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
Avelo Airlines
7.5
Good
Alaska Airlines
8.0
Very good
11,219 reviews

Comfort

7.8

Boarding

8.1

Food

7.1

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.
American Airlines
7.2
Good
11,034 reviews
Alaska Airlines
8.0
Very good
11,219 reviews

Comfort

7.8

Boarding

8.1

Food

7.1

Overall

8.0

Entertainment

7.0

Crew

8.5

Reviews

1 / 20
6.0
Good

Hannah,Aug 2025

SFO - SAN

Ticket said TSA pre check, but then the TSA agent said that Alaska Airlines has not actually entered the pre check information for the ticket, so I had to use regular security. During boarding, I have a disability and need to board early. The Alaska Airlines employee announced disability boarding, but then immediately announced 2 other groups to board, so I still had to fight the crowds. On the plane, the stewardess was brusk and rude. Seats were very uncomfortable, especially on lower back.

Related info for your journey

Find useful and relevant information for your journey from Santa Rosa to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How popular is this Santa Rosa to Ontario flight route?

    Within the past month, 1 users have taken a look at flights from Santa Rosa Sonoma County to Ontario.

  • How long is the flight from Santa Rosa to Ontario?

    Airlines like Alaska Airlines fly from Santa Rosa to Ontario in about 1h 27m. The time it takes to get you to your destination is usually consistent. The distance between Santa Rosa and Ontario is about 423 mi. Generally, flights for this route are nonstop.

  • What are the cheapest airlines flying from Santa Rosa to Ontario round-trip?

    Avelo Airlines, at $55, was found to be the cheapest airline from Santa Rosa to Ontario.Alternate airlines to your destination round-trip include Alaska Airlines and American Airlines. Avelo Airlines is priced at 75% lower than the current average price of a flight leaving 3 months from now.

  • Can I find deals for flights from Santa Rosa to Ontario that include hotel bookings?

    Yes. In addition to deals on Santa Rosa to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Santa Rosa to Ontario?

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

  • Can I find deals for business class flights from Santa Rosa to Ontario?

    Yes. Cheapflights offers flight deals from Santa Rosa to Ontario 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 Santa Rosa to Ontario?

    Currently, February is the cheapest month in which you can book a flight from Santa Rosa to Ontario (average of $19). Flying from Santa Rosa to Ontario in July is currently the most expensive (average of $57). 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.

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Top 3 airlines flying from Santa Rosa to Ontario

Discover the top 3 airlines that operate flights from Santa Rosa to Ontario. 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 2,558,603 searches. Data last updated October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
Avelo AirlinesCheapest$55Average$79FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$157Average$357FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$222Average$299FlexibilityNo cancel feeOn-time71%

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