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$159+ 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 10/1. Fares are subject to change and may not be available on all flights or dates of travel.
STS — ONT
oct. 17 — oct. 241
vie. 10/17
vie. 10/24
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 septiembre 17, 2025.

Round-trip from

$237
(American Airlines)

One-way from

$159
(American Airlines)

Popular in

June

Cheapest in

December

Average price

$281
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. 24% potential increase in price ($68 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($9 potential savings vs. average RT price).
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Average for round-trip flights in September 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 septiembre 17, 2025.

This American Airlines deal was found by Cheapflights users on 9/14. 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.
mié. 10/812:53 pmSTS - ONT
1 stop5h 42mAmerican Airlines
mar. 10/146:15 amONT - STS
1 stop6h 06mAmerican Airlines
Deal found 9/14$237
This American Airlines deal was found by Cheapflights users on 9/15. 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.
mié. 10/812:53 pmSTS - ONT
1 stop5h 42mAmerican Airlines
sáb. 10/1110:09 amONT - STS
1 stop5h 38mAmerican Airlines
Deal found 9/15$238
This American Airlines deal was found by Cheapflights users on 9/15. 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.
lun. 9/294:19 pmSTS - ONT
1 stop5h 29mAmerican Airlines
lun. 10/66:15 amONT - STS
1 stop6h 06mAmerican Airlines
Deal found 9/15$257
This American Airlines deal was found by Cheapflights users on 9/14. 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.
jue. 10/24:19 pmSTS - ONT
1 stop5h 29mAmerican Airlines
lun. 10/66:15 amONT - STS
1 stop6h 06mAmerican Airlines
Deal found 9/14$258
This American Airlines deal was found by Cheapflights users on 9/15. 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.
mié. 10/11:00 pmSTS - ONT
1 stop5h 16mAmerican Airlines
dom. 10/56:10 amONT - STS
1 stop6h 19mAmerican Airlines
Deal found 9/15$278
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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.
mié. 11/122:22 pmSTS - ONT
1 stop6h 31mAlaska Airlines
sáb. 11/154:11 pmONT - STS
1 stop5h 54mAlaska Airlines
Deal found 9/16$291
This American Airlines deal was found by Cheapflights users on 9/15. 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.
sáb. 10/1112:53 pmSTS - ONT
1 stop5h 42mAmerican Airlines
sáb. 10/2510:09 amONT - STS
1 stop5h 38mAmerican Airlines
Deal found 9/15$297
This Alaska Airlines deal was found by Cheapflights users on 9/16. 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.
mar. 10/72:30 pmSTS - ONT
1 stop9h 33mAlaska Airlines
mié. 10/156:00 amONT - STS
1 stop7h 36mAlaska Airlines
Deal found 9/16$302
This Alaska Airlines deal was found by Cheapflights users on 9/17. 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.
mié. 10/222:30 pmSTS - ONT
1 stop9h 33mAlaska Airlines
lun. 11/36:11 pmONT - STS
1 stop19h 15mAlaska Airlines
Deal found 9/17$312

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 septiembre 17, 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

mié. 10/8

12:53 pm-6:35 pm

1 stop5h 42m

Ontario

sáb. 10/11

10:09 am-3:47 pm

1 stop5h 38m

$237

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

mar. 10/7

12:53 pm-6:35 pm

1 stop5h 42m

Ontario

mar. 10/14

10:09 am-3:47 pm

1 stop5h 38m

$237

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

vie. 2/27

4:18 pm-9:40 pm

1 stop5h 22m

Ontario

mar. 3/3

6:46 am-12:14 pm

1 stop5h 28m

$297

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

lun. 10/6

12:53 pm-6:59 pm

1 stop6h 06m

Ontario

mar. 10/7

10:09 am-3:47 pm

1 stop5h 38m

$298

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

mar. 10/7

2:30 pm-12:03 am

1 stop9h 33m

Ontario

mié. 10/15

6:00 am-1:36 pm

1 stop7h 36m

$302

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

mié. 10/8

2:30 pm-12:03 am

1 stop9h 33m

Ontario

mié. 10/15

6:00 am-10:06 pm

1 stop16h 06m

$302

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

mié. 10/15

7:05 am-12:37 pm

1 stop5h 32m

Ontario

mié. 10/22

1:31 pm-10:06 pm

1 stop8h 35m

$302

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

mié. 10/22

2:30 pm-12:03 am

1 stop9h 33m

Ontario

lun. 11/3

6:11 pm-1:26 pm

1 stop19h 15m

$312

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

mié. 10/1

1:00 pm-6:16 pm

1 stop5h 16m

$159

Santa RosaOntario

STS - ONT

STSONT

Santa Rosa Sonoma County

jue. 10/16

4:17 pm-9:49 pm

1 stop5h 32m

$169

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 15 results
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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, August is the cheapest month in which you can book a flight from Santa Rosa to Ontario (average of $246). Flying from Santa Rosa to Ontario in March is currently the most expensive (average of $327). 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 septiembre 17, 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.

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 septiembre 17, 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
10,000 reviews

Entertainment

7.1

Food

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

Boarding

8.1

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
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

Boarding

8.1

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
10,000 reviews

Entertainment

7.1

Food

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

Boarding

8.1

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
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Overall

8.0

Comfort

7.8

Crew

8.5

Boarding

8.1

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 American Airlines and Alaska Airlines fly from Santa Rosa to Ontario in about 5h 42m. The time it takes to get you to your destination can typically vary by up to 3h 51m. The distance between Santa Rosa and Ontario is about 423 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    Avelo Airlines, at $57, 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 73% 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, August is the cheapest month in which you can book a flight from Santa Rosa to Ontario (average of $246). Flying from Santa Rosa to Ontario in March is currently the most expensive (average of $327). 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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Alternative routes for Santa Rosa to Ontario

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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 septiembre 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
Avelo AirlinesCheapest$57Average$80FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$177Average$321FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$222Average$299FlexibilityNo cancel feeOn-time71%

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