HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Detroit

$76+ Cheap flights from Seattle to Detroit Metropolitan Wayne County Airport (SEA - DTW)

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 4/23. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — DTW
Feb 24 — Mar 31
Mon 2/24
Mon 3/3
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Seattle to Detroit 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.

The best prices from Seattle/Tacoma Intl to Detroit Metropolitan Wayne County are usually found in January or February, booked 90 days in advance, depart on a Wednesday or Thursday and return on a Wednesday

Cheap flight deals from Seattle to Detroit

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Detroit (DTW). 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 February 19, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$228
(FlightHub)

One-way from

$76
(CheapOair)

Popular in

November

Cheapest in

January

Average price

$322

Good round-trip deal

$326 or less

Good one-way deal

$196 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Detroit Metropolitan Wayne County flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Detroit Metropolitan Wayne County flights.
Search Deals
From Seattle/Tacoma Intl to Detroit Metropolitan Wayne County
Search Deals
One-way flight from Seattle/Tacoma Intl to Detroit Metropolitan Wayne County
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($71 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2025
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to Detroit Metropolitan Wayne County.
Search Deals
Price to beat on a one-way flight from Seattle/Tacoma Intl to Detroit Metropolitan Wayne County.
Search Deals

Find flight deals from Seattle to Detroit

Cheapest flights from Seattle to Detroit
Explore the most affordable flight options available from Seattle to Detroit. Find the lowest fares from popular airlines and budget airlines, with prices last updated on February 19, 2025.

This FlightHub deal was found by Cheapflights users on 2/19. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/179:06 pmSEA - DTW
1 stop11h 52mSpirit Airlines
Tue 4/2212:22 pmDTW - SEA
1 stop10h 39mSpirit Airlines
Deal found 2/19$233
This Alaska Airlines deal was found by Cheapflights users on 2/18. 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.
Wed 3/128:25 amSEA - DTW
Nonstop4h 28mAlaska Airlines
Wed 3/195:10 pmDTW - SEA
Nonstop4h 59mAlaska Airlines
Deal found 2/18$237
This Booking.com deal was found by Cheapflights users on 2/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/11:37 pmSEA - DTW
1 stop13h 21mMultiple Airlines
Sat 6/76:18 amDTW - SEA
1 stop12h 04mMultiple Airlines
Deal found 2/17$238
This Delta deal was found by Cheapflights users on 2/19. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/87:10 amSEA - DTW
1 stop9h 26mDelta
Sat 4/1212:15 pmDTW - SEA
Nonstop5h 00mDelta
Deal found 2/19$247
This Mytrip deal was found by Cheapflights users on 2/17. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/186:01 pmSEA - DTW
1 stop8h 15mFrontier
Thu 3/62:43 pmDTW - SEA
1 stop24h 19mFrontier
Deal found 2/17$263
This Sun Country Air deal was found by Cheapflights users on 2/18. 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 Sun Country Air is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/1011:59 pmSEA - DTW
1 stop6h 06mSun Country Air
Fri 7/1810:05 amDTW - SEA
1 stop15h 45mSun Country Air
Deal found 2/18$320
This American Airlines deal was found by Cheapflights users on 2/18. 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.
Tue 3/1112:59 amSEA - DTW
1 stop10h 19mAmerican Airlines
Sat 3/154:49 pmDTW - SEA
Nonstop5h 07mAmerican Airlines
Deal found 2/18$342
This United Airlines deal was found by Cheapflights users on 2/19. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/83:24 pmSEA - DTW
2 stops14h 45mUnited Airlines
Wed 4/162:10 pmDTW - SEA
1 stop7h 51mUnited Airlines
Deal found 2/19$352
This Trip.com deal was found by Cheapflights users on 2/18. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/48:45 amSEA - DTW
Nonstop4h 19mHawaiian Airlines
Fri 4/115:10 pmDTW - SEA
Nonstop4h 59mHawaiian Airlines
Deal found 2/18$369
This JetBlue deal was found by Cheapflights users on 2/19. 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 JetBlue is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/711:48 pmSEA - DTW
1 stop9h 11mJetBlue
Mon 3/1012:45 pmDTW - SEA
1 stop12h 53mJetBlue
Deal found 2/19$372

Find flights from Seattle to Detroit within your budget

Customize your flight search to find flights from Seattle to Detroit 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 February 19, 2025.

Fly from

Seattle

Fly to

Detroit

Route

Depart

Return

Price

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Thu 4/17

9:06 pm-11:58 am

1 stop11h 52m

Detroit Metropolitan Wayne County

Tue 4/22

12:22 pm-8:01 pm

1 stop10h 39m

$233

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Wed 3/12

10:55 pm-6:18 am

Nonstop4h 23m

Detroit Metropolitan Wayne County

Sat 3/15

8:30 am-10:42 am

Nonstop5h 12m

$237

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Sun 6/1

1:37 pm-5:58 am

1 stop13h 21m

Detroit Metropolitan Wayne County

Sat 6/7

6:18 am-3:22 pm

1 stop12h 04m

$238

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Tue 4/8

8:45 am-4:04 pm

Nonstop4h 19m

Detroit Metropolitan Wayne County

Fri 4/11

5:10 pm-7:09 pm

Nonstop4h 59m

$257

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Thu 7/10

11:59 pm-9:05 am

1 stop6h 06m

Detroit Metropolitan Wayne County

Fri 7/18

10:05 am-10:50 pm

1 stop15h 45m

$320

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Tue 3/11

12:59 am-2:18 pm

1 stop10h 19m

Detroit Metropolitan Wayne County

Sat 3/15

4:49 pm-6:56 pm

Nonstop5h 07m

$342

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Wed 3/5

5:41 pm-5:16 am

1 stop8h 35m

Detroit Metropolitan Wayne County

Mon 3/10

6:00 am-5:53 pm

1 stop14h 53m

$350

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Tue 4/8

3:24 pm-9:09 am

2 stops14h 45m

Detroit Metropolitan Wayne County

Wed 4/16

2:10 pm-7:01 pm

1 stop7h 51m

$352

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Fri 4/4

8:45 am-4:04 pm

Nonstop4h 19m

Detroit Metropolitan Wayne County

Fri 4/11

5:10 pm-7:09 pm

Nonstop4h 59m

$366

SeattleDetroit

SEA - DTW

SEADTW

Seattle/Tacoma Intl

Fri 3/7

11:48 pm-11:59 am

1 stop9h 11m

Detroit Metropolitan Wayne County

Mon 3/10

12:45 pm-10:38 pm

1 stop12h 53m

$372

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/19

Showing 1-10 of 21 results
1
2
3

Compare providers for flights from Seattle to Detroit

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 Seattle to Detroit in February.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
MytripPrice Accuracy3 starsTrust Score*3 stars
CheapOairPrice Accuracy1 starTrust Score*3 stars
FlightsMojoPrice Accuracy-Trust Score*3 stars
Kiwi.comPrice Accuracy3 starsTrust Score*2 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 Seattle-Detroit Metropolitan Wayne County Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Detroit Metropolitan Wayne County Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Detroit Metropolitan Wayne County Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Detroit Metropolitan Wayne County Airport flights, Cheapflights users trust FlightHub the most. FlightHub 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 Seattle-Detroit Metropolitan Wayne County Airport 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 Seattle to Detroit

Have a flexible travel schedule? Discover the best time to fly to Detroit from Seattle 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.

Travel insights for flights from Seattle to Detroit

Get recent, data-driven insights about flights from Seattle to Detroit including ideal travel times, pricing trends, and more.

How far ahead should I book a flight from Seattle to Detroit Metropolitan Wayne County Airport?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Detroit. Price data was last updated on February 14, 2025.

The best time to book flights from Seattle to Detroit Metropolitan Wayne County Airport is 90 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Seattle to Detroit Metropolitan Wayne County Airport?

Currently, April is the cheapest month in which you can book a flight from Seattle to Detroit Metropolitan Wayne County Airport (average of $257). Flying from Seattle to Detroit Metropolitan Wayne County Airport in March is currently the most expensive (average of $305). 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 SEA to DTW?

Find hourly flight availability from Seattle to Detroit. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated February 19, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Detroit Metropolitan Wayne County Airport in the afternoon. If you’re flexible enough to do this you can expect to save up to 15% on your trip compared to booking a flight at noon.

What is the cheapest day to fly from Seattle to Detroit Metropolitan Wayne County Airport?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Detroit. Price data was last updated on February 16, 2025.

Travelers seeking maximum savings on their Seattle to Detroit Metropolitan Wayne County Airport flight should consider departing on Wednesday afternoons when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Seattle to Detroit Metropolitan Wayne County Airport

Explore weekly flight availability from Seattle to Detroit. 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 February 19, 2025.

The most flights from SEA to DTW are scheduled on a Monday (16 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (10 on average).

Rainfall in Detroit by month

Plan your trip to Detroit by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Detroit Metropolitan Wayne County Airport ranges from 1.8 - 3.1 inches per month. August is typically the wettest month, when rainfall can reach 3.1 in. January is typically the driest time to visit Detroit Metropolitan Wayne County Airport when rainfall is around 1.8 in.

Temperature in Detroit by month

Plan your trip to Detroit by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Detroit Metropolitan Wayne County Airport, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 24.8 F).

Reviews of airlines servicing Detroit

Get insights into the airlines that provide service to Detroit. 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 Detroit. Reviews last updated February 19, 2025.
Get a feel of what it's like to fly with Southwest, Alaska Airlines and Delta from Seattle to Detroit by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,413 reviews

Entertainment

7.6

Crew

8.7

Overall

8.1

Food

7.1

Comfort

8.1

Boarding

8.2

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Southwest
8.1
Very good
4,413 reviews
Southwest
8.1
Very good
4,413 reviews

Entertainment

7.6

Crew

8.7

Overall

8.1

Food

7.1

Comfort

8.1

Boarding

8.2

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Alaska Airlines
8.0
Very good
9,691 reviews
Southwest
8.1
Very good
4,413 reviews

Entertainment

7.6

Crew

8.7

Overall

8.1

Food

7.1

Comfort

8.1

Boarding

8.2

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Delta
8.0
Very good
8,236 reviews
Southwest
8.1
Very good
4,413 reviews

Entertainment

7.6

Crew

8.7

Overall

8.1

Food

7.1

Comfort

8.1

Boarding

8.2

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Hawaiian Airlines
7.9
Good
2,317 reviews
Southwest
8.1
Very good
4,413 reviews

Entertainment

7.6

Crew

8.7

Overall

8.1

Food

7.1

Comfort

8.1

Boarding

8.2

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

JetBlue
7.4
Good
3,074 reviews
Southwest
8.1
Very good
4,413 reviews

Entertainment

7.6

Crew

8.7

Overall

8.1

Food

7.1

Comfort

8.1

Boarding

8.2

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Detroit. 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 Seattle to Detroit?

    If you book a flight from Seattle to Detroit, you will be flying from Seattle/Tacoma Intl to Detroit Metropolitan Wayne County. Flights to Detroit Metropolitan Wayne County (DTW) from Seattle/Tacoma Intl (SEA) take 4h 10m for a nonstop flight. There are 12 flights from Seattle/Tacoma Intl to Detroit per day from 6 airlines.

  • What are the cheapest airlines flying from Seattle to Detroit Metropolitan Wayne County Airport round-trip?

    Cheapflights users have booked flights from Seattle to Detroit Metropolitan Wayne County Airport round-trip from $230. Other airlines that can offer you cheap pricing are Spirit Airlines, from $233, and Alaska Airlines, from $237. Users have found that Frontier is 42% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from Seattle to Detroit Metropolitan Wayne County Airport one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $76. Users have also found prices from $86 and $119 on Spirit Airlines and Delta, respectively.

  • What are the most reliable airlines from Seattle to Detroit Metropolitan Wayne County Airport?

    No one likes to see their flight delayed. When booking a flight from Seattle to Detroit Metropolitan Wayne County Airport consider choosing Virgin Atlantic (96%), Air France (92%) or Delta (92%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Seattle to Detroit Metropolitan Wayne County Airport?

    On average you can expect to pay $734 for a flight from Seattle to Detroit Metropolitan Wayne County Airport. The cheapest flight overall is $128 while the most popular route, (Seattle/Tacoma Intl - Detroit Metropolitan Wayne County) is currently priced at $173.

  • Can I find deals for flights from Seattle to Detroit that include hotel bookings?

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

  • How can I find direct flights from Seattle to Detroit?

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

  • Can I find deals for business class flights from Seattle to Detroit?

    Yes. Cheapflights offers flight deals from Seattle to Detroit 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 Seattle to Detroit Metropolitan Wayne County Airport?

    Currently, April is the cheapest month in which you can book a flight from Seattle to Detroit Metropolitan Wayne County Airport (average of $257). Flying from Seattle to Detroit Metropolitan Wayne County Airport in March is currently the most expensive (average of $305). 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 Seattle?

Book flights to Seattle if you plan to visit one of these locations
Warren
Sterling Heights
Dearborn
Novi
Waterford
Troy
Southfield
Belleville
Romulus
Clarkston
Utica
Plymouth
Monroe
Livonia
Ypsilanti
Wixom
Auburn Hills
Put-in-Bay
Chelsea
Brighton

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.

Top 6 airlines flying from Seattle to Detroit

Discover the top 6 airlines that operate flights from Seattle to Detroit. 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 February 19, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$147Average$215FlexibilityNo cancel feeOn-time62%
American AirlinesCheapest$150Average$446FlexibilityNo cancel feeOn-time71%
Spirit AirlinesCheapest$173Average$382FlexibilityNo cancel feeOn-time65%
Alaska AirlinesCheapest$202Average$429FlexibilityNo cancel feeOn-time75%
DeltaCheapest$244Average$440FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$301Average$500FlexibilityNo cancel feeOn-time69%
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.