HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Norfolk

$62+ Cheap flights from Cincinnati to Norfolk (CVG - ORF)

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 5/15. Fares are subject to change and may not be available on all flights or dates of travel.
CVG — ORF
May 23 — May 301
Sat 5/23
Sat 5/30
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Cincinnati to Norfolk 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 Cincinnati Cinci./N. Kentucky to Norfolk are usually found in July or August, booked 43 days in advance, depart on a Monday or Tuesday and return on a Tuesday

Cheap flight deals from Cincinnati to Norfolk

Cheapest flights from Cincinnati to Norfolk
Explore the most affordable flight options available from Cincinnati to Norfolk. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 23, 2026.

This Kiwi.com deal was found by Cheapflights users on 4/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/1512:54 pm
CVG
-
ORF
1 stop22h 32m
Frontier
Sun 7/1912:21 pm
ORF
-
CVG
1 stop23h 28m
Frontier
Deal found 4/21$123
This Kiwi.com deal was found by Cheapflights users on 4/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/1912:54 pm
CVG
-
ORF
1 stop22h 27m
Frontier
Wed 6/2412:21 pm
ORF
-
CVG
1 stop22h 53m
Frontier
Deal found 4/18$126
This Kiwi.com deal was found by Cheapflights users on 4/22. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/1712:54 pm
CVG
-
ORF
1 stop22h 32m
Frontier
Wed 6/2412:21 pm
ORF
-
CVG
1 stop22h 53m
Frontier
Deal found 4/22$127
This Kiwi.com deal was found by Cheapflights users on 4/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/1812:46 pm
CVG
-
ORF
1 stop22h 25m
Frontier
Mon 5/2512:06 pm
ORF
-
CVG
1 stop22h 58m
Frontier
Deal found 4/20$132
This Kiwi.com deal was found by Cheapflights users on 4/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/1512:54 pm
CVG
-
ORF
1 stop22h 32m
Frontier
Mon 7/2012:21 pm
ORF
-
CVG
1 stop22h 53m
Frontier
Deal found 4/21$139
This Frontier deal was found by Cheapflights users on 4/23. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/159:30 pm
CVG
-
ORF
1 stop20h 59m
Frontier
Mon 5/189:12 pm
ORF
-
CVG
1 stop26h 17m
Frontier
Deal found 4/23$140
This Kiwi.com deal was found by Cheapflights users on 4/18. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/1912:54 pm
CVG
-
ORF
1 stop22h 27m
Frontier
Tue 6/239:35 pm
ORF
-
CVG
1 stop26h 11m
Frontier
Deal found 4/18$147
This Kiwi.com deal was found by Cheapflights users on 4/23. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/1512:46 pm
CVG
-
ORF
1 stop22h 09m
Frontier
Tue 5/1912:06 pm
ORF
-
CVG
2 stops25h 11m
Frontier
Deal found 4/23$153
This Kiwi.com deal was found by Cheapflights users on 4/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 6/612:46 pm
CVG
-
ORF
1 stop22h 25m
Frontier
Fri 6/1212:21 pm
ORF
-
CVG
1 stop23h 26m
Frontier
Deal found 4/19$154
This Kiwi.com deal was found by Cheapflights users on 4/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/1812:46 pm
CVG
-
ORF
1 stop22h 25m
Frontier
Thu 5/219:12 pm
ORF
-
CVG
1 stop15h 50m
Frontier
Deal found 4/21$170
This Kiwi.com deal was found by Cheapflights users on 4/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/1512:46 pm
CVG
-
ORF
1 stop22h 09m
Multiple Airlines
Mon 5/187:44 pm
ORF
-
CVG
1 stop17h 23m
Multiple Airlines
Deal found 4/20$171

Find flight deals from Cincinnati to Norfolk

Discover tips and strategies to find the most affordable flight options for your journey from Cincinnati (CVG) to Norfolk (ORF). 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 April 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$123
(Kiwi.com)

One-way from

$62
(Kiwi.com)

Popular in

March

Cheapest in

July

Average price

$346

Good round-trip deal

$100 or less

Good one-way deal

$88 or less
Provider with most accurate pricing for Cincinnati Cinci./N. Kentucky-Norfolk flight deals.
Search Deals
Provider most trusted by Cheapflights users for Cincinnati Cinci./N. Kentucky-Norfolk flights.
Search Deals
From Cincinnati Cinci./N. Kentucky to Norfolk
Search Deals
One-way flight from Cincinnati Cinci./N. Kentucky to Norfolk
Search Deals
Highest demand for flights based on searches. 23% potential increase in price ($98 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($13 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals
Price to beat on a round-trip flight from Cincinnati Cinci./N. Kentucky to Norfolk.
Search Deals
Price to beat on a one-way flight from Cincinnati Cinci./N. Kentucky to Norfolk.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Cincinnati to Norfolk 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 April 23, 2026.
Use the filters below to find and compare flights from Cincinnati to Norfolk that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Tue 5/12

4:03 pm-9:04 pm

1 stop5h 01m

Norfolk

Wed 5/13

6:05 am-1:10 pm

1 stop7h 05m

$270

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Fri 5/15

6:00 pm-11:15 pm

1 stop5h 15m

Norfolk

Tue 5/19

6:00 am-9:40 am

1 stop3h 40m

$276

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Thu 5/28

6:00 am-9:39 am

1 stop3h 39m

Norfolk

Mon 6/1

4:57 pm-11:59 pm

1 stop7h 02m

$343
Quickest round-trip

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Thu 6/18

5:30 am-9:20 am

1 stop3h 50m

Norfolk

Sat 6/20

6:55 pm-10:40 pm

1 stop3h 45m

$347

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Thu 6/11

3:30 pm-10:42 pm

1 stop7h 12m

Norfolk

Fri 6/19

7:59 pm-12:40 am

1 stop4h 41m

$347

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Tue 7/7

4:16 pm-9:43 pm

1 stop5h 27m

Norfolk

Fri 7/10

7:59 pm-12:39 am

1 stop4h 40m

$347

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Fri 6/19

5:30 pm-10:42 pm

1 stop5h 12m

Norfolk

Sun 6/21

6:05 am-9:49 am

1 stop3h 44m

$347
Cheapest one-way

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Tue 6/9

5:34 am-11:27 am

1 stop5h 53m

$114

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Thu 4/30

5:20 pm-5:05 pm

1 stop23h 45m

$123

CincinnatiNorfolk

CVG - ORF

CVGORF

Cincinnati Cinci./N. Kentucky

Thu 5/21

5:48 am-11:33 am

1 stop5h 45m

$174

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/21

Showing 1-10 of 14 resultsSorted by cheapest first
1
2

Compare providers for flights from Cincinnati to Norfolk

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 Cincinnati to Norfolk in April.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust 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 Cincinnati-Norfolk flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Cincinnati-Norfolk flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Cincinnati-Norfolk flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Cincinnati-Norfolk 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 Cincinnati-Norfolk 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 Cincinnati to Norfolk

Have a flexible travel schedule? Discover the best time to fly to Norfolk from Cincinnati 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 Cincinnati to Norfolk

How far ahead should I book a flight from Cincinnati to Norfolk?

Use this chart to determine the optimal time to book a round-trip flight from Cincinnati to Norfolk. Price data was last updated on April 17, 2026.

The price you pay for your flight from Cincinnati to Norfolk may vary depending on when you book. For the best chance of a lower fare, look to book 43 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from Cincinnati to Norfolk?

Currently, July is the cheapest month in which you can book a flight from Cincinnati to Norfolk (average of $170). Flying from Cincinnati to Norfolk in March is currently the most expensive (average of $466). 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 CVG to ORF?

Find hourly flight availability from Cincinnati to Norfolk. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated April 23, 2026.

One of the essential ways to save on airfare from Cincinnati to Norfolk is to remain as flexible as possible. Flights that are in the morning tend to be the most expensive. A flight in the evening could potentially save you up to 64% on airfare.

How much does it cost to fly round-trip from Cincinnati to Norfolk?

Reviews of airlines servicing Norfolk

Get insights into the airlines that provide service to Norfolk. 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 Norfolk. Reviews last updated April 23, 2026.
Read through reviews of airlines operating flights from Cincinnati to Norfolk, such as Southwest,Delta, andUnited Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,330 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,330 reviews
Southwest
8.0
Very good
4,330 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Delta
7.9
Good
8,439 reviews
Southwest
8.0
Very good
4,330 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
United Airlines
7.4
Good
9,637 reviews
Southwest
8.0
Very good
4,330 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Allegiant Air
7.3
Good
707 reviews
Southwest
8.0
Very good
4,330 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
American Airlines
7.1
Good
11,662 reviews
Southwest
8.0
Very good
4,330 reviews

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Cincinnati to Norfolk. 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 Cincinnati to Norfolk flight route?

    The Cincinnati Cinci./N. Kentucky to Norfolk flight path was viewed by 1 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Cincinnati to Norfolk?

    A quick flight from Cincinnati to Norfolk can take about 5h 01m. United Airlines provides one of the quickest options available for as low as $270. There are 484 mi between Cincinnati and Norfolk. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Cincinnati to Norfolk round-trip?

    According to our current data, Allegiant Air ($60), Frontier ($186), and Southwest ($187) offers the cheapest pricing from Cincinnati to Norfolk. Allegiant Air is priced at 81% lower than the current average price of a flight leaving 3 months from now.

  • What are the cheapest airlines to fly from Cincinnati to Norfolk one-way?

    The cheapest airlines for a one-way flight from Cincinnati to Norfolk are Allegiant Air ($50), Southwest ($95), and American Airlines ($98).

  • What are the cheapest flights from Cincinnati to Norfolk?

    Looking at all options, your cheapest flight can be booked for $69. While the most popular route (Cincinnati Cinci./N. Kentucky - Norfolk) can be booked for $176 on average, our data indicates $95 when flying from Cincinnati to Norfolk.

  • Can I find deals for flights from Cincinnati to Norfolk that include hotel bookings?

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

  • How can I find direct flights from Cincinnati to Norfolk?

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

  • Can I find deals for business class flights from Cincinnati to Norfolk?

    Yes. Cheapflights offers flight deals from Cincinnati to Norfolk 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 Cincinnati to Norfolk?

    Currently, July is the cheapest month in which you can book a flight from Cincinnati to Norfolk (average of $170). Flying from Cincinnati to Norfolk in March is currently the most expensive (average of $466). 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 Norfolk?

Book flights to Norfolk if you plan to visit one of these locations
Kill Devil Hills
Portsmouth
Nags Head
Suffolk
Kitty Hawk
Manteo

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 Cincinnati to Norfolk

See prices for flight routes from nearby airports that may be better suited for you.
Detroit to Dulles Intl flights
Detroit to Reagan-National flights
Cincinnati to Reagan-National flights
Cincinnati to Dulles Intl flights
Detroit to Raleigh flights
Cleveland to Dulles Intl flights
Columbus to Dulles Intl flights
Pittsburgh to Dulles Intl flights
Cleveland to Reagan-National flights
Detroit to Norfolk flights
Cleveland to Raleigh flights
Columbus to Reagan-National flights
Cincinnati to Raleigh flights
Detroit to Richmond flights
Dayton to Reagan-National flights
Pittsburgh to Reagan-National flights
Pittsburgh to Raleigh flights
Detroit to Greensboro flights
Dayton to Dulles Intl flights
Akron to Reagan-National flights
Akron to Raleigh flights
Akron to Norfolk flights
Cleveland to Norfolk flights
Akron to Dulles Intl flights
Columbus to Norfolk flights
Columbus to Raleigh flights
Cincinnati to Greensboro flights
Cleveland to Greensboro flights
Cincinnati to Richmond flights
Cleveland to Richmond flights
Detroit to Roanoke flights
Pittsburgh to Richmond flights
Dayton to Norfolk flights
Pittsburgh to Norfolk flights
Columbus to Richmond flights
Dayton to Raleigh flights
Pittsburgh to Greensboro flights
Akron to Richmond flights
Akron to Greensboro flights
Dayton to Greensboro flights
Detroit to Charlottesville flights
Dayton to Richmond flights
Columbus to Greensboro flights
Cincinnati to Charlottesville flights
Cleveland to Charlottesville flights
Erie to Raleigh flights
Pittsburgh to Blountville flights

Top 6 airlines flying from Cincinnati to Norfolk

Discover the top 6 airlines that operate flights from Cincinnati to Norfolk. 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 April 23, 2026.
AirlineCheapestAverageFlexibilityOn-time
Allegiant AirCheapest$60Average$95FlexibilityNo cancel feeOn-time88%
FrontierCheapest$186Average$290FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$187Average$346FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$196Average$333FlexibilityNo cancel feeOn-time71%
DeltaCheapest$198Average$396FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$286Average$346FlexibilityNo 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.