Millions of people will be flying out from the UK on holiday this year, and travellers may want to be aware of the best and worst times to travel.
Delays around certain weeks of the year could prove to be an annoyance due to the high volume of people also travelling, as well as the potential costs.
If you want the greatest chance of avoiding those sorts of issues, there are more effective weeks to fly out.
Research from the travel search engine KAYAK has looked into this to find the best way to avoid high costs and delays.
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The best and worst weeks to fly out from the UK in 2026
To come to its conclusions, KAYAK looked into flight searches made on the site between July 2024 and December 2025 for journeys departing throughout 2025 from any UK airport.
Prices included were average prices for economy, return tickets.
From this research, patterns emerged over what prices and airport passenger volume might look like for 2026.
KAYAK stressed that prices may vary and savings cannot be guaranteed.
The best week to fly out from the UK for this year is considered to be August 31 to September 6.
Meanwhile, the worst week is December 21-27 over the busy Christmas holiday period.
Rachel Mumford, UK Travel Expert at KAYAK, said: “Being flexible and avoiding peak travel times like the height of summer and the Christmas rush could save travellers hundreds of pounds.
“Based on last year’s pricing trends, the most expensive period to fly this year will be Christmas with average flight prices reaching their highest point in 2025 for both domestic and international travel at £512 and £850 respectively.
“For May to August, domestic prices rose from late spring into early summer, peaking at £393 in the second half of May.
“International fares were highest at the height of summer, with prices reaching £655 in late July and remaining high at £636 in early August.
“Barring any significant shifts in demand, these seasonal peaks are likely to follow a comparable pattern this year.”
The ‘Shoulder Season’ of late August into early September was considered to be the best time to fly.
Mumford added: “Internationally, prices in 2025 fell to £362, the lowest point of the second half of the year.
“Domestic fares also dropped after the summer peak, with average prices dropping to £171, making early autumn a more budget-friendly time to fly as we move away from the main school holiday period.”
Best and worst times to fly this summer
KAYAK’s Summer Check-in Report has shared a number of destinations that will be cheap to travel to this summer.
Discussing the best time to fly out for this period, Mumford explained: “International return tickets are around one-third of peak summer prices, averaging just £209 in the week commencing September 7 and £238 the week prior, compared with £690 in the week commencing July 13 and £694 in the week commencing July 20.
“This makes late August and early September the clear sweet spot for value-conscious travellers this summer.
“Those who can dodge peak weeks stand to save significantly, with more left to spend on the ground.”
When are you planning to fly out from the UK this year, and has this advice been brought into your travel plans? Let us know in the comments.
