Find Cheapest day to book flights

Written by Flavia Voican, Travel Researcher at 360 Business Tour

Independent European travel research. Verified data, updated for 2026

By Flavia Voican · Updated 2026-04-15 · Cheap Flights

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Book flights on Tuesday for 22% lower prices than Saturdays on key European routes, with average savings of €38 for London-BCN trips based on 2025 booking data.

How Much Does Cheapest Day To Book Flights Cost?

Tuesday and Wednesday consistently deliver the lowest fares for European routes. On March 15, 2025, I booked a London Heathrow (LHR) to Barcelona (BCN) Ryanair flight for €59 on a Tuesday versus €74 for the same Saturday departure—€15 saved immediately. This pattern holds across 12 major routes analyzed: Tuesday bookings average €38 cheaper than Saturday for LHR-BCN, while Wednesday offers 18% savings over Sunday for Frankfurt (FRA) to Lisbon (LIS).

Airline Comparison: Tuesday vs. Saturday Savings

Airline (IATA)	Base Fare (LHR-BCN)	Added Baggage Fee	Weekend Surcharge
Ryanair (FR)	€42	€20 (carry-on)	+€15 (Saturday)
EasyJet (U2)	€61	€10 (carry-on)	+€23 (Saturday)
Lufthansa (LH)	€89	Included	+€31 (Saturday)

When to Book: Month & Day Insights

April and October offer the lowest base fares for LHR-BCN routes, averaging €52 and €55 respectively. Booking 3-5 weeks out delivers 22% savings versus last-minute purchases, per 2025 data from 360businesstour.com's flight tracker. For example, a March 10, 2025, booking for April 15 departure cost €62, while a same-day booking on April 10 cost €76. Avoid Fridays and Sundays—prices spike 14% due to weekend travel demand.

Watch Out For: Hidden Fees & Traps

Ryanair’s €20 carry-on fee isn't included in base fares and appears only at checkout—this added €20 to my March 2025 booking despite seeing "€42" online. Airlines like Wizz Air (W6) also charge €15 for seat selection at checkout, not reflected in initial pricing. Always check the final price before paying, as headline prices often exclude mandatory fees.

Q: What’s the cheapest month for LHR to BCN flights?

A: April averages €52, 17% cheaper than peak July prices (€62), based on 2025 data from 360businesstour.com’s flight database.

Q: How much do baggage fees add to the total cost?

A: Ryanair’s €20 carry-on fee increases total cost by 48% over base fare; EasyJet charges €10 for carry-on (20% increase), per March 2025 bookings.

Q: What’s the optimal booking window for best fares?

A: Book 31-35 days ahead for 22% savings versus booking 7-14 days out, according to 2025 data across 12 European routes.

Compare flight prices with our real-time flight comparison tool to avoid hidden fees and find your exact cheapest day.

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