Two people can sit side by side on the same flight and have paid very different prices. Much of the difference comes down to when they booked. There's no single magic day, but there are booking windows that work far better than others, and a few peak periods where waiting almost always costs you. Here's a simple timeline to follow, plus the habits that save money every time.
Why fares go up and down
Airlines sell seats on each flight in price bands. The cheapest bands are released first and sell out as the flight fills, so fares tend to rise as departure gets closer — especially on busy routes and dates. Fares also move with demand: school holidays, festivals and long weekends push prices up, and airlines run sales when they want to fill quieter flights. That's why the right time to book depends on where and when you're going, not on a fixed rule.
The booking timeline at a glance
| Type of trip | Good time to book | Why |
|---|---|---|
| Short domestic flight, off-peak | 1–3 months ahead | Plenty of seats; prices usually rise in the last few weeks |
| Short international (e.g. within Asia or Europe) | 1–4 months ahead | Budget airlines release cheap seats early and run regular sales |
| Long-haul holiday | 3–6 months ahead | Fewer flights and seats, so cheap fares go sooner |
| Peak season (Christmas, summer holidays, Easter) | 4–8 months ahead | Demand is high and late fares are rarely cheap |
| Tết and Lunar New Year | 3–5 months ahead, or as soon as dates are known | Flights home sell out and fares climb steadily |
These are typical windows, not guarantees. A sale can beat them, and an unusually popular route can sell out sooner. The rule of thumb: the busier the dates, the earlier you should book.
Peak holidays: book early, don't wait for a bargain
Christmas and New Year
For flights between mid-December and early January, aim to book by September or October. Last-minute Christmas deals are rare: the flights fill up whatever the price. If your dates are flexible, flying on Christmas Day itself or in the first days of January is often noticeably cheaper than the weekend before Christmas.
Summer and school holidays
School holiday dates are known months ahead, and so are the price rises. For a July or August family trip, start looking in winter or early spring. If you can travel just before or just after the school holidays, the same trip can cost much less.
Tết and Lunar New Year
Tết 2027 falls in early February. Flights home in the week before Tết and back to the cities afterwards are among the busiest of the year, and the cheapest seats go early. Book as soon as you know your dates, watch for extra Tết flights that airlines often add, and consider flying a few days earlier or later than everyone else.
Which days to fly (and which day to book)
- The day you fly matters more than the day you book. Tuesdays, Wednesdays and Saturdays are often cheaper than Fridays and Sundays, when weekend and business travellers fly.
- Early-morning and late-night flights are often cheaper than mid-morning or early-evening departures.
- Return dates count too. Coming back on a Tuesday instead of a Sunday can save as much as moving your outbound flight.
- Most search sites have a flexible dates or price calendar view. Use it before you settle on dates.
Myths to ignore
“Always book on a Tuesday”
This used to have some truth when airlines loaded new fares on set days. Today prices change constantly, so the day of the week you press “book” matters far less than how far ahead you book and which days you fly.
“Prices go up because you searched before”
Many people clear cookies or use private browsing to stop prices rising. Fares change because seats sell and demand moves, and a fare you saw yesterday may simply be gone. Searching in a private window does no harm, but it isn't a reliable way to get a lower price.
“Last minute is always cheapest”
For package holidays this is sometimes true. For flights it usually isn't: the last seats on a full flight tend to be the most expensive. Last-minute bargains exist mainly on quiet routes out of season.
Set a price alert and decide on a target
The easiest way to book at the right time is to let prices come to you:
- Pick your dates and route, with a little flexibility if you can.
- Check the current price and decide what you're happy to pay.
- Set a price alert so you get an email when the fare drops. On our trip planner, Trip ForMe, you can set one straight from the flights in your chat.
- Book when the price hits your target, or when your booking window above is closing. Don't wait for a perfect low that may never come.
Booking a flight to or from the United States? US rules require airlines to let you cancel for free within 24 hours (or hold the fare) when you book at least seven days before departure, so you can lock in a good price while you double-check plans. Other countries and airlines have different rules, so check the fare conditions before you pay.
Count the whole price, not just the fare
A cheap fare isn't cheap if you add a checked bag, a seat and a meal at the airport. Before you compare, check:
- Baggage: many budget fares include only a small cabin bag.
- Airport location and transfers: a cheaper flight into a far-away airport can cost more once you add the taxi or bus.
- Change and refund rules: a flexible fare can be worth a little more if your plans might move.
When to book your stay
Accommodation follows the same pattern as flights: the best-value places in popular towns go first, especially over holidays and festivals. A good approach:
- Book a place with free cancellation as soon as your flights are set, so you have somewhere good secured.
- Keep an eye on the price. On HomeStayForMe stays you can tap “Watch price” in the trip planner and we'll email you if the price for your dates drops.
- Look at nights midweek. Many homestays charge less from Sunday to Thursday than on Friday and Saturday nights.
Ready to look? Browse homestays, or see when to go and where to stay in our destination guides.
The short version
- Book short trips 1–3 months ahead, long-haul 3–6 months, and peak holidays 4–8 months ahead.
- For Tết, book as soon as you know your dates.
- Fly midweek or early in the morning when you can.
- Set a price alert, decide your target price, and book when you hit it.
- Compare the full cost, bags and transfers included.
For more ways to save, read our guide to finding cheap flights.
Cover photo by Edwin Petrus on Unsplash.
