HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Portland

$84+ Cheap flights from Burbank to Portland (BUR - PDX)

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 2/24. Fares are subject to change and may not be available on all flights or dates of travel.
BUR — PDX
Dec 26 — Jan 21
Fri 12/26
Fri 1/2
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Burbank to Portland with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Burbank Bob Hope to Portland are usually found in January or February, booked 77 days in advance, depart on a Saturday or Wednesday and return on a Wednesday

Find flight deals from Burbank to Portland

Cheapest flights from Burbank to Portland
Explore the most affordable flight options available from Burbank to Portland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on November 26, 2025.

This Alaska Airlines deal was found by Cheapflights users on 11/26. 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 12/257:04 amBUR - PDX
Nonstop2h 36mAlaska Airlines
Mon 1/510:45 amPDX - BUR
Nonstop2h 20mAlaska Airlines
Deal found 11/26$157
This Cheapflightsfares deal was found by Cheapflights users on 11/25. 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.
Wed 12/179:13 amBUR - PDX
1 stop4h 37mAlaska Airlines
Sun 1/184:51 pmPDX - BUR
1 stop4h 49mAlaska Airlines
Deal found 11/25$162
This Alaska Airlines deal was found by Cheapflights users on 11/24. 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.
Mon 12/156:09 pmBUR - PDX
1 stop5h 37mAlaska Airlines
Tue 12/1610:40 amPDX - BUR
1 stop5h 32mAlaska Airlines
Deal found 11/24$166
This Cheapflightsfares deal was found by Cheapflights users on 11/25. 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 12/255:10 pmBUR - PDX
1 stop5h 49mAlaska Airlines
Wed 12/315:57 pmPDX - BUR
Nonstop2h 23mAlaska Airlines
Deal found 11/25$190
This Alaska Airlines deal was found by Cheapflights users on 11/26. 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 12/257:00 amBUR - PDX
1 stop5h 13mAlaska Airlines
Sun 1/48:16 amPDX - BUR
Nonstop2h 20mAlaska Airlines
Deal found 11/26$198
This Cheapflightsfares deal was found by Cheapflights users on 11/23. 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.
Fri 12/125:59 pmBUR - PDX
Nonstop2h 29mAlaska Airlines
Sun 12/141:34 pmPDX - BUR
1 stop5h 00mAlaska Airlines
Deal found 11/23$205
This Southwest deal was found by Cheapflights users on 11/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/177:25 amBUR - PDX
1 stop6h 30mSouthwest
Mon 12/295:50 amPDX - BUR
1 stop4h 45mSouthwest
Deal found 11/25$209
This Cheapflightsfares deal was found by Cheapflights users on 11/26. 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 12/187:04 amBUR - PDX
Nonstop2h 36mAlaska Airlines
Thu 1/18:16 amPDX - BUR
Nonstop2h 20mAlaska Airlines
Deal found 11/26$210

Cheap flight deals from Burbank to Portland

Discover tips and strategies to find the most affordable flight options for your journey from Burbank (BUR) to Portland (PDX). 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 November 26, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$157
(Alaska Airlines)

One-way from

$84
(Delta)

Popular in

November

Cheapest in

January

Average price

$321

Good round-trip deal

$216 or less

Good one-way deal

$133 or less
Provider with most accurate pricing for Burbank Bob Hope-Portland flight deals.
Search Deals
Provider most trusted by Cheapflights users for Burbank Bob Hope-Portland flights.
Search Deals
From Burbank Bob Hope to Portland
Search Deals
One-way flight from Burbank Bob Hope to Portland
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($10 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals
Price to beat on a round-trip flight from Burbank Bob Hope to Portland.
Search Deals
Price to beat on a one-way flight from Burbank Bob Hope to Portland.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Burbank to Portland 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 November 26, 2025.
Use the filters below to find and compare flights from Burbank to Portland that are best for you.

Fly from

Burbank

Fly to

Portland

Route

Depart

Return

Price

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Tue 1/6

7:04 am-9:40 am

Nonstop2h 36m

Portland

Thu 1/8

5:55 pm-8:12 pm

Nonstop2h 17m

$157

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Tue 1/13

10:44 am-4:50 pm

1 stop6h 06m

Portland

Mon 1/26

1:38 pm-6:42 pm

1 stop5h 04m

$163

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Tue 1/27

9:50 am-8:59 pm

2 stops11h 09m

Portland

Sat 1/31

7:10 am-4:08 pm

2 stops8h 58m

$167

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Mon 1/5

7:04 am-9:40 am

Nonstop2h 36m

Portland

Fri 1/9

1:38 pm-6:42 pm

1 stop5h 04m

$167

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Mon 1/12

7:10 am-9:40 am

Nonstop2h 30m

Portland

Fri 1/23

5:35 pm-9:58 pm

1 stop4h 23m

$167

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Wed 12/31

6:07 pm-8:36 pm

Nonstop2h 29m

Portland

Sun 1/4

8:16 am-10:36 am

Nonstop2h 20m

$212

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Sat 1/10

9:50 am-6:50 pm

2 stops9h 00m

Portland

Mon 1/12

5:00 pm-9:58 pm

1 stop4h 58m

$219

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Thu 12/11

4:46 pm-12:04 am

1 stop7h 18m

Portland

Tue 12/16

5:05 pm-9:52 pm

1 stop4h 47m

$222

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Sun 12/21

4:40 pm-11:20 pm

1 stop6h 40m

Portland

Tue 12/30

6:20 am-12:50 pm

1 stop6h 30m

$229

BurbankPortland

BUR - PDX

BURPDX

Burbank Bob Hope

Thu 2/12

8:29 am-11:46 pm

2 stops15h 17m

Portland

Sun 2/15

2:49 pm-5:10 pm

Nonstop2h 21m

$234

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/24

Showing 1-10 of 18 results
1
2

Compare providers for flights from Burbank to Portland

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 Burbank to Portland in November.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
CheapfaremartPrice Accuracy-Trust Score*1 star
CheapTicketsDealPrice 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 Burbank-Portland flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Burbank-Portland flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Burbank-Portland flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Burbank-Portland 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 Burbank-Portland 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 Burbank to Portland

Have a flexible travel schedule? Discover the best time to fly to Portland from Burbank 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 Burbank to Portland

How far ahead should I book a flight from Burbank to Portland?

Use this chart to determine the optimal time to book a round-trip flight from Burbank to Portland. Price data was last updated on November 21, 2025.

To ensure you get the cheapest price possible for a flight from Burbank to Portland, you should look to book at least 77 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Burbank to Portland?

Currently, March is the cheapest month in which you can book a flight from Burbank to Portland (average of $42). Flying from Burbank to Portland in November is currently the most expensive (average of $112). 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 BUR to PDX?

Find hourly flight availability from Burbank to Portland. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 26, 2025.

One of the essential ways to save on airfare from Burbank to Portland is to remain as flexible as possible. Flights that are in the evening tend to be the most expensive. A flight at noon could potentially save you up to 3% on airfare.

What is the cheapest day to fly from Burbank to Portland?

Use this chart to determine the cheapest time to fly round-trip from Burbank to Portland. Price data was last updated on November 25, 2025.

Travelers seeking maximum savings on their Burbank to Portland flight should consider departing on Friday evenings when fares are most often at their lowest. Saturday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

The best insider tips for Burbank to Portland flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
Cheapflights partnered with top experts to bring you the best recommendations for your Burbank to Portland trip
Airlines
Alaska Airlines

Alaska's Premium Class offers extra legroom and free cocktails, enhancing comfort.


Alaska's Wi-Fi is a flat fee, great for work on short flights.

Read more about Alaska Airlinesby Robert Schrader
Spirit Airlines

Spirit's Big Front Seats offer 11 inches more legroom, ideal for short flights.


Spirit's self-service bag drop saves time; print boarding pass beforehand to avoid fees.

Read more about Spirit Airlinesby Daniel Scheffler
Airports
BUR

Hollywood Burbank Airport is known for its fast security lines. Arrive at least one hour ahead, but it's usually a quick process.

Read more about BURby Emily Zemler
PDX

Use the MAX red line light rail for a convenient 40-minute trip from PDX to downtown Portland. Trains arrive every 15 minutes.

Read more about PDXby Brandon Schultz
Our travel experts
Robert Schrader

Robert Schrader

Expert on Alaska Airlines

Robert Schrader

Robert Schrader

One of the web's original travel bloggers, Robert launched his first site Leave Your Daily Hell in 2009. Since then, he's expanded into destination niche sites (one each for Japan, Thailand and Taiwan), in addition to having written for the inflight magazines of Singapore Airlines and Korean Air. Overall, he's visited nearly 100 countries, and flies business as often as possible.

Read more
Daniel Scheffler

Daniel Scheffler

Expert on Spirit Airlines

Daniel Scheffler

Daniel Scheffler

Daniel Scheffler is a travel writer, podcaster, and producer. Born in Africa, bred in Europe and now living in America he has traveled to 140 countries (and all 50 U.S. states). Plus he has stayed at over 2500 hotels across the globe. His original shows Everywhere and Without Maps (available on Spotify) showcase his beliefs, travel is about humanity and sharing that beauty. And thus it reminds you that you shouldn’t believe everything you think.

Read more
Brandon Schultz

Brandon Schultz

Expert on PDX

Brandon Schultz

Brandon Schultz

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more
Emily Zemler

Emily Zemler

Expert on BUR

Emily Zemler

Emily Zemler

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more

Reviews of airlines servicing Portland

Get insights into the airlines that provide service to Portland. 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 Portland. Reviews last updated November 26, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest, and Hawaiian Airlines from Burbank to Portland by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
11,358 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

LAX - LIH

The staff were exceptional! They all were kind, accommodating, and professional.
Alaska Airlines
8.0
Very good
11,358 reviews
Alaska Airlines
8.0
Very good
11,358 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

LAX - LIH

The staff were exceptional! They all were kind, accommodating, and professional.
Southwest
8.0
Very good
4,253 reviews
Alaska Airlines
8.0
Very good
11,358 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

LAX - LIH

The staff were exceptional! They all were kind, accommodating, and professional.
Hawaiian Airlines
7.8
Good
2,815 reviews
Alaska Airlines
8.0
Very good
11,358 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

LAX - LIH

The staff were exceptional! They all were kind, accommodating, and professional.
Spirit Airlines
6.3
Okay
8,159 reviews
Alaska Airlines
8.0
Very good
11,358 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

LAX - LIH

The staff were exceptional! They all were kind, accommodating, and professional.
Frontier
5.8
Fair
3,100 reviews
Alaska Airlines
8.0
Very good
11,358 reviews

Food

7.1

Boarding

8.1

Comfort

7.8

Crew

8.5

Entertainment

7.0

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Anonymous,Nov 2025

LAX - LIH

The staff were exceptional! They all were kind, accommodating, and professional.

Related info for your journey

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

  • What airports do I use to fly from Burbank to Portland?

    Booking a flight from Burbank Bob Hope (BUR) to Portland (PDX) is your only option if you wish to fly from Burbank to Portland. On a typical day, there are 3 flights from Bob Hope to Portland, all of which are around 2h 24m for a nonstop flight. You can also purchase a plane ticket from 5 airlines when you book a flight from Bob Hope to Portland.

  • How popular is this Burbank to Portland flight route?

    Flights from Burbank Bob Hope to Portland have been viewed 9 times in the past calendar month.

  • How long is the flight from Burbank to Portland?

    Airlines like Alaska Airlines and Delta fly from Burbank to Portland in about 2h 36m. The time it takes to get you to your destination can typically vary by up to 8h 33m. The distance from Burbank to Portland is about 817 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from Burbank to Portland round-trip?

    Currently priced at $68, Frontier will fly you from Burbank to Portland and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Spirit Airlines and Alaska Airlines - these airlines can fly you to your destination from $96 and $157, respectively. Frontier is priced at 74% lower than the current average price of a flight leaving 3 months from now.

  • What are the most reliable airlines from Burbank to Portland?

    The top 3 most reliable airlines when flying from Burbank to Portland are Horizon Air (100%), British Airways (92%) and Hawaiian Airlines (88%).

  • What are the cheapest flights from Burbank to Portland?

    On average you can expect to pay $508 for a flight from Burbank to Portland. The cheapest flight overall is $88 while the most popular route, (Burbank Bob Hope - Portland) is currently priced at $117.

  • Can I find deals for flights from Burbank to Portland that include hotel bookings?

    Yes. In addition to deals on Burbank to Portland flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Burbank to Portland?

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

  • Can I find deals for business class flights from Burbank to Portland?

    Yes. Cheapflights offers flight deals from Burbank to Portland 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 Burbank to Portland?

    Currently, March is the cheapest month in which you can book a flight from Burbank to Portland (average of $42). Flying from Burbank to Portland in November is currently the most expensive (average of $112). 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

Traveling to a place near Portland?

Book flights to Portland if you plan to visit one of these locations
Vancouver
Seaside
Clackamas
Lincoln City
Lake Oswego
Beaverton
McMinnville
Hillsboro
Troutdale
Cannon Beach
Long Beach
Longview
Tigard
The Dalles
Depoe Bay
Stevenson
Wilsonville
Pacific City
Gresham
Tillamook

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Burbank to Portland

See prices for flight routes from nearby airports that may be better suited for you.
Los Angeles to Portland flights
San Francisco to Portland flights
Ontario to Portland flights
San Diego to Portland flights
Los Angeles to Boise flights
Los Angeles to Redmond flights
San Jose to Portland flights
Santa Ana to Portland flights
Sacramento to Portland flights
Oakland to Portland flights
San Francisco to Boise flights
Las Vegas to Portland flights
San Francisco to Redmond flights
San Francisco to Eugene flights
Fresno to Portland flights
Palm Springs to Portland flights
Burbank to Boise flights
Los Angeles to Medford flights
San Diego to Boise flights
Santa Ana to Boise flights
Reno to Portland flights
Ontario to Boise flights
Santa Rosa to Portland flights
Ontario to Eugene flights
San Luis Obispo to Portland flights
Medford to Portland flights
Las Vegas to Boise flights
Los Angeles to Eugene flights
Sacramento to Boise flights
San Jose to Boise flights
Palm Springs to Redmond flights
Long Beach to Portland flights
Burbank to Redmond flights
Fresno to Boise flights
San Francisco to Medford flights
Burbank to Eugene flights
San Diego to Redmond flights
Santa Ana to Redmond flights
Ontario to Medford flights
Santa Barbara to Portland flights
Ontario to Redmond flights
San Diego to Medford flights
Sacramento to Eugene flights
San Diego to Eugene flights
Burbank to Medford flights
Santa Ana to Medford flights
Medford to Boise flights
Oakland to Boise flights
San Luis Obispo to Eugene flights

Top 5 airlines flying from Burbank to Portland

Discover the top 5 airlines that operate flights from Burbank to Portland. 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 November 26, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$68Average$156FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$96Average$196FlexibilityNo cancel feeOn-time65%
Alaska AirlinesCheapest$156Average$276FlexibilityNo cancel feeOn-time75%
Hawaiian AirlinesCheapest$177Average$268FlexibilityNo cancel feeOn-time85%
SouthwestCheapest$206Average$376FlexibilityNo cancel feeOn-time63%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.