$456 Find Cheap Flights from Knoxville to Portugal

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Knoxville to Portugal departing on 5/4. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

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Cheap Flights from Knoxville to Portugal

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Lisbon
Lisbon2 stops$668
Porto
Porto2 stops$1,133
Lisbon
Lisbon2 stops$668
Porto
Porto2 stops$1,133

Book Cheap Knoxville to Portugal Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Knoxville to Portugal that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Knoxville to Portugal

Sa, Apr 25 - Fr, Mai 8
United Airlines Logo
7:20 pm - 8:20 am
TYS
-
LIS
32h 00m
2 stops
United Airlines Logo
12:20 pm - 2:34 pm
LIS
-
TYS
31h 14m
1 stop
$668United Airlines
Di, Apr 21 - Di, Apr 28
Lufthansa Logo
5:53 pm - 2:30 pm
TYS
-
FAO
39h 37m
2 stops
Lufthansa Logo
3:55 pm - 11:08 pm
FAO
-
TYS
36h 13m
2 stops
$729Lufthansa
Di, Apr 21 - Mi, Apr 29
Lufthansa Logo
5:53 pm - 2:30 pm
TYS
-
FAO
39h 37m
2 stops
Lufthansa Logo
3:55 pm - 4:49 pm
FAO
-
TYS
53h 54m
2 stops
$735Lufthansa
Mo, Apr 20 - Mo, Apr 27
United Airlines Logo
11:25 am - 2:30 pm
TYS
-
FAO
22h 05m
2 stops
United Airlines Logo
3:25 pm - 10:34 pm
FAO
-
TYS
36h 09m
2 stops
$745United Airlines
Sa, Apr 25 - Fr, Mai 8
United Airlines Logo
9:40 am - 10:35 am
TYS
-
LIS
19h 55m
1 stop
United Airlines Logo
12:20 pm - 2:34 pm
LIS
-
TYS
31h 14m
1 stop
$765United Airlines
So, Apr 5 - Sa, Apr 18
United Airlines Logo
9:40 am - 10:30 am
TYS
-
LIS
19h 50m
1 stop
United Airlines Logo
6:15 am - 7:42 pm
LIS
-
TYS
18h 27m
2 stops
$784United Airlines
So, Apr 5 - Sa, Apr 18
Delta Logo
3:13 pm - 2:35 pm
TYS
-
LIS
18h 22m
2 stops
Delta Logo
5:35 am - 10:59 pm
LIS
-
TYS
22h 24m
2 stops
$799Delta
So, Apr 5 - Sa, Apr 18
United Airlines Logo
2:25 pm - 10:30 am
TYS
-
LIS
15h 05m
1 stop
United Airlines Logo
11:25 am - 10:34 pm
LIS
-
TYS
40h 09m
2 stops
$801United Airlines
Sa, Sep 19 - Mi, Sep 30
British Airways Logo
8:39 pm - 6:05 pm
TYS
-
LIS
16h 26m
2 stops
British Airways Logo
7:20 am - 7:04 pm
LIS
-
TYS
16h 44m
2 stops
$841British Airways
Fr, Apr 3 - Fr, Apr 17
United Airlines Logo
7:20 pm - 10:30 am
TYS
-
LIS
10h 10m
1 stop
United Airlines Logo
5:05 am - 10:34 pm
LIS
-
TYS
22h 29m
2 stops
$842United Airlines
Booking Insights

KAYAK's insights & trends for Knoxville to Portugal flights

Get data-powered insights and trends into flights from Knoxville to Portugal to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest month to fly from Knoxville to Portugal?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Knoxville to Portugal, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Knoxville to Portugal is February, when tickets cost $480 (return) on average. On the other hand, the most expensive months are June and May, when the average cost of round-trip tickets is $1,865 and $1,335 respectively.

Good to know

Low seasonFebruary
Cheapest flight$456
Best time to beat the crowds with an average 51% drop in price.
Most popular time to fly and prices are also 19% lower on average.
Flight from Knoxville to Lisbon

FAQs - booking Portugal flights

  • How does KAYAK find such low prices on flights from Knoxville to Portugal?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Knoxville to Portugal.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Knoxville to Portugal?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Knoxville to Portugal is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Knoxville to Portugal?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from Knoxville to Portugal with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Knoxville to Portugal?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from Knoxville to Portugal up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 3 airlines serving from Knoxville to Portugal

 
Need help choosing which airline to fly with from Knoxville to Portugal? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 9462 reviews
7.3Comfort
6.6Food
8.1Crew
7.1Entertainment
7.7Boarding
Airline reviews

No seat back entertainment. And app had a hard time getting entertainment loaded.

8.0 ExcellentStephanie, Mar 2026
DEN - CUN
Read more United Airlines reviews

No seat back entertainment. And app had a hard time getting entertainment loaded.

ticket agent lady wás very helpful , she arranged wheel chair for my elderly mother

Didn't make the flight because the first leg of my flight was canceled and the next leg was already booked.

My flight was canceled a few hours before boarding. I was rebooked on Copa airlines and missed an important meeting .

Good quick flight on a small but comfortable plane. I'm 6'3 and had plenty of space.

Experience was great - no complaints. Took off on time, landed early. Got to the gate relatively quickly - took a little bit of extra time to deplane but nothing excessive.

Business class seats felt very cramped compared to other airlines.

Economy plus was so cramped I could not use my laptop. It was beyond bad.

OK, we were delayed and had to de plane and reboard.

United is one airline which regardless of how many separate United tickets in existence, if one flight breaks down, the airline will take care of all the flights.

The experience at checkin for my American Airlines flight from Sacramento to LAX was very good including the assistance I received in getting my bags checked in and boarding passes printed. Was pleasantly surprised the my bags were checked through all the way to my destination at Clark International Airport in Angeles, Philippines.

Absolutely terrible. Would never fly American again. 2 deplaned incidents and delayed by close to 24 hours. $12 meal voucher for first class passengers was an insult to the injury. Pathetic.

Terrible planning. And even worse gate agents. Absolutely rude behavior.

Half of the TSA checkpoints at PHL are closed. Also, there is no standby for first class passengers. You can only standby for coach. Very dated policy and inconsistent with peers.

Flight was scheduled at 11:26am but they keep Delaying until midnight. They waited at airport restless.

Rough flight No beverage service due to turbulence Bottom Seat cushion was non existent

Great experience. Good dinner and service. FA's were very nice and attentive.

It was great. Smooth flight, comfortable, left on time and landed on time.

Perhaps this is an airport issue, but being in a takeoff queue for over an hour in the taxiing lane is unacceptable. We will definitely be seeking alternative avenues for air travel in the future.

We hoarded. Then we deplaned. Then we waited for 10 hours in the MSP airport due to a wheel misfunction. We understand safety but communication between crew and airport staff was horrible. When we did finally board, we were rushed on and because we were waiting for a “fresh” pilot and crew, we sat in a roasting plane with no A/C for an hour. My question is why was this flight not cancelled right away when they knew this would be a huge issue OR, why did AA not get a substitute plane, considering this was already a full flight? To me, this appears to be a complete breakdown in leadership and utter systems failure. The compensation for completely disrupting travel plans for hundreds, which we paid dearly for, was measly. While we appreciated the lodging for the night, $12 in meal vouchers isn’t going to sustain anyone for over 12 hours. “We apologize; our hands are tied” is no longer an acceptable explanation. We are so completely turned off by this experience and will definitely seek alternative avenues when we need to fly.

WiFi wasn’t available to economy until the end of the flight.

Very good staff members with sincere passion and responsibility in their job.

We paid for Business Class seats, but system did not have us and they were not available.

Very please with the seating that the Kayak staff booked for us!

Worth every penny to upgrade to BC. Treated and felt more like First Class

I paid for a very expensive Business Class seat to and from Cairo Egypt from Charleston SC. There was partnership from states to London using American Airlines. That leg was amazing. The British Airlines leg was a joke. They used the standard no leg room 3 by 3 seats. A tray was put on the middle seat. The trip was 5 hours, from London to Cairo, thus my BC purchase. There was no screen proving tv/movie options, only a small device plug. The fold down tray and the bag of peanuts were typical of normal short run flying. The one toilet was located in the galley. We all got to know each other well. This was my first and last trip with British Airlines. I now understand why they would NEVER give me a seat chart so that I could make a selection.prior to departure. It honestly would not have made a difference, there were less than 50% of occupied seats. Apparently everyone got the memo but me. I have never felt so cheated as with that trip, got to so another going back to London, yeah. I will be sending a letter to customer service and asking for a refund. I will be photos comparing the two BC legs. OH, one more thing. The FC ticket holders got bulkhead and exit row seats. I know they had to be thrilled

Good service, food and comfort in World Traveller Plus. Entertainment was poor - no wifi on the way out and barely working on the way back. Not a great choice of entertainment on the seat back tv.

Late! Late and late! More than 1hr 30mn. This sucks when it is the last of a 4 flight journey. I missed my dinner! Which is not nice on Valentine’s Day!!! But better than the gate next to us, the poor Chinese people were rebooked to the next day flight. AA had to call security as it became very heated with the passengers! It was a mess at DFW that afternoon/evening. I wish they had some food for the people who travel as part of international journey. Indigo does it in India and it is fantastic.

They had us seating down for one hour just waiting on the plane

Flying with BA is always a good experience—even in economy class. It is better if in business and first class. Timely, breeze through security and timely connections

Everything you need to know for your flight from Knoxville to Portugal

Information on your arrival and departure airports