7 ways you're overpaying for flights

Flights are expensive, but there's no need to pay over the odds.

Some airline websites are so confusing that you can end up paying much more than you need.

Our research has found easy ways to save money and get the best flight deals in 2026 while avoiding mistakes that can bump up prices.

Read on to find out when to book, which days to avoid flying, the pitfalls of booking bundled fares, and why you should never let an airline convert the currency when you’re paying for a fare.

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Buying a bundle

Airlines want you to pay for as many extras as possible, so they often provide a default 'regular' or ‘basic’ fare that includes two cabin bags for every person on the booking, seat selection and so-called 'speedy boarding'.

But 'speedy boarding' often just means you're at the front of a queue in the corridor waiting to board. A family of four is unlikely to need to take eight cabin bags between them (particularly if some of the family are small children).

Most airlines will seat passengers together without them having to pay. 

If you actually want any of those extras, pay for them separately. It's likely to be cheaper.

Paying to sit together – even with a decent airline

As above, most airlines will automatically seat you with your travel companions without charging. The only major exceptions are Ryanair and Wizz Air. In our airline survey, we found they were much more likely to split up passengers than BA, easyJet or Jet2. 

Check how likely your airline is to seat you with your family.

Letting the airline do your currency conversion

When you book a one-way flight inbound to the UK, you should be charged in the currency of the country you're flying from. Never agree to be charged in pounds. It might seem simpler but it means that the airline will be converting the currency for you – and that's likely to be worse than the conversion rate you'll get from your bank.

With Ryanair, it's ridiculously complicated to ensure that it doesn't apply its dynamic currency conversion – but by following our guide here, you can opt out.

Flying on a Friday when you don't need to 

Google Flights and Skyscanner will show you a graph of the cheapest days to fly during your chosen month. Fridays and Sundays are typically the most expensive; Tuesdays are typically the cheapest.

Of course, Tuesdays aren't convenient for many people, but you will probably save money on a weekend break if you fly out on a Saturday and come back on a Monday, rather than going Friday to Sunday. You miss the same amount of time at work but could save hundreds.

Booking your flights too early – or too late

You might assume that the earlier you book, the better – but this isn't true.

Skyscanner has a tool that analyses when flights to some popular destinations were cheapest over the past 18 months. It shows that you're rarely better off booking more than six months in advance. 

For example, it suggests that for flights from London to Bangkok at Christmas, the best deals last year were around five weeks before departure, in mid-November.

You can try the tool on the Skyscanner website.

Travelling when everybody else does

For 13 out of 16 short-haul destinations we looked at last year, January was the cheapest month to fly. This is for obvious reasons: most people want guaranteed good weather on the Spanish Costas or Greek islands. However, you don't need hot sun to enjoy the food and culture of cities such as Barcelona, Lisbon or Seville. 

Average temperatures are likely to be much higher than in the UK in January, and you've got a good chance of getting a bargain.

Ryanair vs easyJet – which budget airline should you choose?

Travelling in the school holidays, when you don't need to

Even families can travel at cheaper times by checking school holiday dates in the rest of the country. 

Half term in London and the South East, for example, is often in a different week from northern England or the Midlands. That means that if you live in Birmingham, you might find a cheaper flight from a London airport when the capital's kids are still at school, although you'll have to factor in the cost of an extra hour and a half or so of travel. There are also big differences in the dates of school summer holidays between England and Scotland.

It's worth checking the Inset (teacher training) days at your children's school. These are often on a Friday or Monday, tagged on to a school holiday, and it will usually be cheaper to fly out on one of those days.

Which are the best airlines for short-haul and long-haul flights?

Forgetting to check alternative airports

Budget airlines are notorious for flying to airports that are nowhere near your destination (Girona and Reus in Spain are both used for flights to Barcelona, despite being around 60 miles north and south, respectively).

But sometimes choosing a secondary airport results in a big saving, with minimal hassle. On the Costa Blanca, you can choose between Alicante and Murcia airports – there's about an hour's drive between them. In countries with fast, relatively inexpensive trains, you could consider spending a night in one town before heading to another. Italy is well connected by train – for example, you can travel between Verona and Venice in just over an hour.

Forgetting that not all airlines include cabin bags

Sometimes the airlines that appear cheapest are much more expensive than the initial price suggests. 

EasyJet, Ryanair and Wizz Air will charge you for any luggage that won't fit under your seat. Last year, we found that this could quadruple the cost of the cheapest Wizz Air flights and more than double the cost of the cheapest easyJet and Ryanair flights. If you want to check luggage into the hold, you'll pay even more.

Airlines such as Jet2 and British Airways, which still don't charge for cabin luggage, may appear more expensive initially, but the price you see on the first page is likely to be what you'll actually pay.

Assuming that booking flights and hotels separately is cheaper

If you plan to book hotel accommodation in a popular destination or resort, it's often cheaper to get a package holiday. In the past, we've found that 70% of all-inclusive holidays are cheaper than buying flights and accommodation separately. You'll also have more legal rights if anything goes wrong, and you'll be refunded by Atol if your travel firm goes bust.