Cheapest Days to Fly: How to Save Big on Flights Every Week

If someone told you that picking a day or two differently could save you enough money on flights to fund an extra night out or a cool tour, would you believe them? Because it’s true—flights can jump or drop as much as £60-£150 overnight, just depending on which day you choose to fly. Yet most travellers, even seasoned ones, keep guessing. Airlines have their own secret sauce for pricing and, turns out, the day you fly might be the most powerful trick to unlock these savings. It isn’t about complicated hacks or expert insider knowledge—it's basically about reading the pattern and knowing when to click 'book.'

Why Flight Prices Change Dramatically By Day

There’s a good reason behind those wild swings in flight prices—but it’s rarely to do with fuel cost or distance. Airlines are obsessed with what’s called “yield management.” Their computers track demand down to the hour for every route. If thirty more people suddenly want seats on a Friday morning flight to Barcelona, the price can spike instantly. The thing is, most people search and book trips around the same routines: they check weekends, they want to start vacations near the end of the work week or come back early Monday to squeeze out more fun time.

Before COVID-19 hit, the trends were already obvious to industry insiders: airlines saw Mondays, Fridays, and Sundays as prime time (high demand). They charge more, because business travellers like flying out Monday and back Friday, while leisure travellers love Thursday evening or Friday departures with Sunday returns. During the pandemic, when business travel fell off a cliff, airline schedules and prices got scrambled everywhere. But by 2023, the same pattern bounced right back. Tuesdays and Wednesdays got less traffic—and prices dropped, simply because fewer people flew those days.

Why does “less traffic” equal cheaper flights? Empty planes cost airlines. Seats that go unsold could mean a loss for that flight. So, airlines set software to drop the price to fill those midweek empties, often last minute but sometimes even weeks out. They’d rather get a lower ticket price than let a seat fly empty. Experts at companies like Skyscanner and Google Flights have tracked these patterns across millions of data points. For over a decade, search results and airline ticket reports have consistently shown: Tuesdays and Wednesdays are almost always the cheapest days to fly, no matter if you’re going long-haul to Asia or hopping a puddle-jumper to Paris.

Here’s a quick look at average price differences, drawn from Hopper’s 2024 Airfare Study and Expedia’s quarterly reports:

While numbers shift by season or current events, Tuesdays and Wednesdays still win for being the lowest. Just a small change in your departure date could save enough for a fancy Airbnb upgrade or another day out.

How to Spot the Cheapest Days When Booking Flights

Knowing which days are cheaper is great, but how do you actually find those deals without spending hours hunting or refreshing your browser until your finger cramps up? Here’s where the real game starts.

First off: use flight comparison tools, but not just one. Skyscanner, Google Flights, and Kayak each have slightly different search engines, and sometimes pulling up the same route on three sites shows three different prices or even slightly different cheap days. The magic trick is turning on their "flexible dates" or "monthly view" feature. This way, you can scan the calendar and see where the cheapest patches light up. Don't be lazy and just pick your "go-to" tool; try at least two for every search (trust me, I’ve seen as much as £88 difference the same week to Lisbon, all because I checked two engines).

Play around with the filter—set your "depart" and "return" anywhere from Sunday to Thursday for the biggest savings. Sometimes flying out Tuesday and returning Thursday costs even less than the bookend return. Airlines usually post their lowest fares about six weeks in advance, but last-minute drops can happen midweek if a flight’s not full. If you’re a risk-taker, checking for Tuesday or Wednesday flights a week ahead can be a goldmine, especially for city breaks or shorter hauls.

Watch out for holidays, though. If there’s a national holiday or school break in your country or at your destination—prices on Tuesdays and Wednesdays can spike. That’s because airlines know the midweek lull disappears when everyone’s heading home for Christmas or cramming in a February half-term ski trip. Don’t take the midweek "rule" at face value around these dates; double-check with every search.

Timing your actual booking matters, too, not just your travel days. Most people hit "buy" on the weekends when they finally have time to dream up a trip or with a glass of wine in hand. Airlines know this and sometimes hike prices early Friday through Sunday just when you’re most likely to be browsing. Regulars in travel forums often swear by booking Tuesdays around noon (when airlines release new fare batches). While not a magic trick, it’s worth trying, especially if you see fares nudging down from the weekend high.

Got a favourite airline? Sign up for their fare alerts or loyalty programmes. Airlines often send exclusive "midweek flash sales" or codes for loyal flyers that drop prices on these quieter days. Following airlines and travel sites on social can also mean catching those "Tuesday-only" promo fares—sometimes only for a few hours.

Here are a few practical tips that work in 2025 (and have done for ages):

• Search for flights in a private/incognito tab to avoid price hikes from repeated searches.
• If you can, fly out and return on a Tuesday or Wednesday. Mix-and-match is fine: a Wednesday departure, Tuesday return, or vice versa.
• Always check at least two comparison tools and directly on the airline’s website for hidden promo prices.
• Don’t forget about very early flights (the dreaded 6am ones) or late-night returns—these are often priced even lower on Tuesdays and Wednesdays.
• Be flexible: even shifting by a single day can make a difference, so use the whole calendar view before fixing your plans.
• Try flying to or from a less popular nearby airport. Sometimes, the Tuesday or Wednesday deal is at an alternate airport just an hour down the road.

Staying vigilant, flexible, and ready to snag a deal gives you a real advantage. The work is in the search, but the reward is more cash left for your trip itself.

Lesser-Known Ways to Double Down on Midweek Flight Savings

Okay, picking a Tuesday or Wednesday flight gives you a head start—but you can stack even more tricks to wring out every last penny of savings. Most people overlook little details that airlines use to squeeze out profit, but if you know what they are, you stand a much better chance.

One smart strategy is to combine airlines on different parts of your journey. Many flight sites let you mix carriers for outbound and inbound journeys. Flying out Tuesday on an ultra-low cost airline and coming back Wednesday on a big flag carrier can often result in savings bigger than sticking to a round-trip ticket on one airline. This works especially well for European trips or short-haul flights. Another sneaky trick is searching one-way tickets instead of round-trip. Sometimes, booking two one-way midweek tickets is less than a single return—crazy but true.

Don’t ignore stopovers or layovers. Non-stop flights might sound amazing (who doesn’t love more sleep?) but adding a single layover during a midweek trip can sometimes drop the price by £40-£150, especially on international routes. Check carefully, though—factor in food, airport costs, and possible visa rules for your layover city. If you’re patient, and don’t mind a 3-hour stopover in Amsterdam on a Wednesday, the savings can be worth it.

If you travel often, it’s smart to check out “hidden city ticketing”—where you book a longer flight that stops in your target city, then just don’t board the last leg. For example, book London-Paris-Vienna (but actually get off in Paris). This hack isn’t officially endorsed by airlines and has some risk (bags can go to the final city), but on a midweek trip, it’s sometimes shockingly cheaper.

Loyalty cards and frequent flyer programmes can also stack up extra deals on Tuesdays and Wednesdays. Many airlines offer double points or special discounts when booking on these quieter days. Even if you’re not a jet-setter, it costs nothing to sign up for free. Before booking, peek at your credit card perks—many offer "cheap day" bonuses on certain online travel agencies (OTAs) that only work on midweek purchases.

Season matters, too. Summer and winter holidays always command higher prices, but in the sweet spot months of late April, May, or September, Tuesday and Wednesday deals are even juicier. During off-peak weeks, less crowded airports mean even more empty seats for sale at a discount. So, double the effect: fly in a quiet week, on a quiet day, and you could see prices almost 40% less than peak Friday or Sunday rates.

Advanced travellers also swear by setting up “price alerts” months in advance for their top destinations, then only booking once the calendar shows the familiar Tuesday/Wednesday dip. Many tools now let you automate alerts for specific days—perfect if you’re eyeing a spontaneous trip but want to leap at the best price. Combine this with tracking prices right after airlines update their schedules (usually Tuesdays at midday, UK time), and you’ll never have to guess when the best sale’s coming.

Finally, sometimes airlines play mind games. If you start your search weeks out and see a certain Tuesday or Wednesday looking low, don’t wait too long—dynamic pricing can pop that fare up within hours. It pays to clear your browser cookies and check again, or use different devices (weird, but airline cookies really do track interest and sometimes raise prices based on repeat lookups).

Long story short? Tuesdays and Wednesdays are the two cheapest days to fly because airlines just want to fill their unsold seats. Pair this with flexible searching, timing, stopovers, loyalty perks, and a dash of courage to try new tools, and you can slash more off ticket costs than most people ever realise. The magic isn’t in being a flight nerd—it’s being alert, flexible, and ready to scoop up what others miss.