HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Portugal

$499+ Cheap flights from Knoxville (TYS) to Portugal

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/8. Fares are subject to change and may not be available on all flights or dates of travel.
TYS — LIS
Jan 26 — Feb 21
Mon 1/26
Mon 2/2
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Knoxville to Portugal 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.

Cheap flight deals from Knoxville to Portugal

Best flights from Knoxville to Portugal
Discover carefully curated flight deals from Knoxville to Portugal that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 27, 2025.

This United Airlines deal was found by Cheapflights users on 12/25. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 2/86:45 amTYS - LIS
2 stops20h 25mUnited Airlines
Sun 2/155:00 amLIS - TYS
2 stops39h 15mUnited Airlines
Deal found 12/25$499
This Delta deal was found by Cheapflights users on 12/25. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 1/1111:54 amTYS - LIS
1 stop15h 06mDelta
Mon 1/1910:00 amLIS - TYS
1 stop30h 12mDelta
Deal found 12/25$612
This oojo deal was found by Cheapflights users on 12/24. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/48:23 pmTYS - LIS
2 stops16h 32mBritish Airways
Mon 5/115:05 pmLIS - TYS
2 stops35h 01mBritish Airways
Deal found 12/24$644
This United Airlines deal was found by Cheapflights users on 12/25. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/252:21 pmTYS - LIS
1 stop14h 54mUnited Airlines
Sun 3/110:50 amLIS - TYS
2 stops28h 59mUnited Airlines
Deal found 12/25$513
This Delta deal was found by Cheapflights users on 12/25. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/55:01 pmTYS - LIS
2 stops19h 49mDelta
Sat 4/185:35 amLIS - TYS
2 stops22h 24mDelta
Deal found 12/25$625
This United Airlines deal was found by Cheapflights users on 12/25. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 1/111:59 pmTYS - LIS
2 stops13h 11mUnited Airlines
Mon 1/1911:20 amLIS - TYS
2 stops38h 32mUnited Airlines
Deal found 12/25$594
This United Airlines deal was found by Cheapflights users on 12/25. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 1/107:20 pmTYS - LIS
2 stops33h 00mUnited Airlines
Mon 1/1911:20 amLIS - TYS
2 stops38h 32mUnited Airlines
Deal found 12/25$596
This United Airlines deal was found by Cheapflights users on 12/25. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 1/76:59 amTYS - LIS
2 stops20h 11mUnited Airlines
Sat 1/1710:15 amLIS - TYS
2 stops14h 12mUnited Airlines
Deal found 12/25$610
This United Airlines deal was found by Cheapflights users on 12/26. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/255:50 amTYS - FAO
2 stops24h 30mUnited Airlines
Mon 6/111:40 amFAO - TYS
2 stops27h 19mUnited Airlines
Deal found 12/26$1,043

Find flight deals from Knoxville to Portugal

Keep the following information in mind while searching for Knoxville to Portugal flight deals. Data was last updated December 27, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$499
(United Airlines)

Popular in

June

Cheapest in

January

Average price

$804
Provider with most accurate pricing for Knoxville McGhee Tyson-Lisbon Humberto Delgado flight deals.
Search Deals
Provider most trusted by Cheapflights users for Knoxville McGhee Tyson-Lisbon Humberto Delgado flights.
Search Deals
From Knoxville McGhee Tyson to Portugal
Search Deals
Highest demand for flights based on searches. 31% potential increase in price ($447 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 7% potential price decrease ($67 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Knoxville to Portugal 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 December 27, 2025.
Use the filters below to find and compare flights from Knoxville to Portugal that are best for you.

Fly from

Knoxville

Fly to

Portugal

Route

Depart

Return

Price

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Sun 2/8

6:45 am-8:10 am

2 stops20h 25m

Lisbon Humberto Delgado

Sun 2/15

5:00 am-3:15 pm

2 stops39h 15m

$499

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Wed 2/25

2:21 pm-10:15 am

1 stop14h 54m

Lisbon Humberto Delgado

Sun 3/1

10:50 am-10:49 am

2 stops28h 59m

$513

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Sun 1/11

1:59 pm-8:10 am

2 stops13h 11m

Lisbon Humberto Delgado

Mon 1/19

11:20 am-8:52 pm

2 stops38h 32m

$594

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Sat 1/10

7:20 pm-9:20 am

2 stops33h 00m

Lisbon Humberto Delgado

Mon 1/19

11:20 am-8:52 pm

2 stops38h 32m

$596

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Wed 1/7

6:59 am-8:10 am

2 stops20h 11m

Lisbon Humberto Delgado

Sat 1/17

10:15 am-7:27 pm

2 stops14h 12m

$610

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Sun 1/11

11:54 am-8:00 am

1 stop15h 06m

Lisbon Humberto Delgado

Mon 1/19

10:00 am-11:12 am

1 stop30h 12m

$612

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Sun 4/5

5:01 pm-5:50 pm

2 stops19h 49m

Lisbon Humberto Delgado

Sat 4/18

5:35 am-10:59 pm

2 stops22h 24m

$625

KnoxvilleLisbon

TYS - LIS

TYSLIS

Knoxville McGhee Tyson

Mon 5/4

8:23 pm-5:55 pm

2 stops16h 32m

Lisbon Humberto Delgado

Mon 5/11

5:05 pm-11:06 pm

2 stops35h 01m

$644

KnoxvilleFaro

TYS - FAO

TYSFAO

Knoxville McGhee Tyson

Mon 5/25

5:50 am-11:20 am

2 stops24h 30m

Faro

Mon 6/1

11:40 am-9:59 am

2 stops27h 19m

$1,043

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/25

Best time to book a flight from Knoxville to Portugal

Have a flexible travel schedule? Discover the best time to fly to Portugal from Knoxville 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 Knoxville to Portugal

What is the cheapest month to book a flight from Knoxville to Portugal?

Currently, December is the cheapest month in which you can book a flight from Knoxville to Portugal (average of $475). Flying from Knoxville to Portugal in May is currently the most expensive (average of $1,125). 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.

Reviews of airlines servicing Portugal

Get insights into the airlines that provide service to Portugal. 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 Portugal. Reviews last updated December 27, 2025.
Peruse reviews from past customers who have flown with United Airlines, American Airlines, and British Airways from Knoxville to Portugal to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,116 reviews

Entertainment

7.1

Overall

7.4

Food

6.6

Crew

8.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.
United Airlines
7.4
Good
9,116 reviews
United Airlines
7.4
Good
9,116 reviews

Entertainment

7.1

Overall

7.4

Food

6.6

Crew

8.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.
American Airlines
7.2
Good
11,069 reviews
United Airlines
7.4
Good
9,116 reviews

Entertainment

7.1

Overall

7.4

Food

6.6

Crew

8.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.
British Airways
6.7
Okay
7,614 reviews
United Airlines
7.4
Good
9,116 reviews

Entertainment

7.1

Overall

7.4

Food

6.6

Crew

8.1

Boarding

7.7

Comfort

7.3

Reviews

1 / 20
10.0
Excellent

Michelle,Dec 2025

DEN - MKE

I liked that the plane waited 5 minutes for a family whose incoming plane was late. This was the last flight of the day to MKE. Flight attendants actually checked in throughout the flight. Although, not really friendly. Happy to see screens on seat backs again. This is my first time not flying first class in over 10 years. It was economy plus.

Related info for your journey

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

  • What airport do you fly from for flights from Knoxville to Portugal?

    For a flight from Knoxville to Portugal, you will be flying from McGhee Tyson. Knoxville McGhee Tyson (TYS) is just 11.3 mi from the center of the city.

  • How long is the flight from Knoxville to Portugal?

    For as low as $499, United Airlines can have you in Portugal from Knoxville in 20h 25m. The distance from Knoxville to Portugal is about 3997 mi.

  • What are the most popular routes from Knoxville to Portugal?

    The most popular flight routes from Knoxville to Portugal are Knoxville McGhee Tyson - Lisbon Humberto Delgado, Knoxville McGhee Tyson - Funchal Madeira and Knoxville McGhee Tyson - Faro.

  • Can I find deals for flights from Knoxville to Portugal that include hotel bookings?

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

  • How can I find direct flights from Knoxville to Portugal?

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

  • Can I find deals for business class flights from Knoxville to Portugal?

    Yes. Cheapflights offers flight deals from Knoxville to Portugal 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 Knoxville to Portugal?

    Currently, December is the cheapest month in which you can book a flight from Knoxville to Portugal (average of $475). Flying from Knoxville to Portugal in May is currently the most expensive (average of $1,125). 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

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 Knoxville to Portugal

See prices for flight routes from nearby airports that may be better suited for you.
Nashville to Heathrow flights
Nashville to Dublin flights
Nashville to Gatwick flights
Nashville to Leonardo da Vinci/Fiumicino flights
Nashville to London City flights
Nashville to Charles de Gaulle flights
Nashville to Orly flights
Nashville to Athens flights
Nashville to Stansted flights
Nashville to Frankfurt flights
Nashville to Lisbon flights
Nashville to Barcelona-El Prat flights
Nashville to Keflavik Intl flights
Nashville to Zurich flights
Nashville to Madrid flights
Nashville to Malpensa flights
Nashville to Edinburgh flights
Knoxville to Heathrow flights
Memphis to Charles de Gaulle flights
Memphis to Gatwick flights
Memphis to Heathrow flights
Memphis to Orly flights
Nashville to Vicenza flights
Nashville to Istanbul flights
Memphis to Leonardo da Vinci/Fiumicino flights
Nashville to Amsterdam flights
Nashville to Prague flights
Nashville to Bruxelles-National flights
Nashville to Linate flights
Nashville to Glasgow Intl flights
Knoxville to Frankfurt flights
Knoxville to Barcelona-El Prat flights
Nashville to Frederic Chopin flights
Knoxville to Charles de Gaulle flights
Knoxville to Leonardo da Vinci/Fiumicino flights
Nashville to Oslo Gardermoen flights
Memphis to Athens flights
Nashville to Sabiha Gokcen flights
Chattanooga to Dublin flights
Knoxville to Dublin flights
Nashville to Naples flights
Nashville to Munich flights
Knoxville to Otopeni Intl flights
Knoxville to Athens flights
Memphis to Keflavik Intl flights
Memphis to London City flights
Nashville to Budapest flights
Nashville to Florence flights
Nashville to Vienna flights
Memphis to Amsterdam flights

Top 3 airlines flying from Knoxville to Portugal

Discover the top 3 airlines that operate flights from Knoxville to Portugal. 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 December 27, 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$477Average$967FlexibilityNo cancel feeOn-time70%
American AirlinesCheapest$602Average$1,004FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$633Average$1,074FlexibilityNo 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.