How shops trick you into spending more, and which of it is illegal.

In November and December 2025, consumer authorities from 23 EU countries went shopping with a checklist and an AI tool. They looked at 314 online traders across the Black Friday period, and one of the things they checked was the crossed-out price. The first number anybody looks at. The European Commission published the results ↗ (opens in new tab) on 26 March 2026. Only 40% fully complied ↗ (opens in new tab) with the EU rules on price reductions. At least 30% didn’t, and the Commission could not tell either way about the rest.

The rule they were failing runs on a 30-day window, takes one sentence, and it has applied since 2022. When a shop in the EU announces a price cut on goods, the “before” price has to be the lowest that shop itself charged in the previous 30 days ↗ (opens in new tab). Not the recommended retail price. Not what it cost last summer.

One sentence of law, and three traders in five did not clearly meet it. The usual advice is to concentrate harder. Your attention was never the weak point. It’s exactly what the design budgets for.

Some of the ways shops trick you into spending more are illegal. Some are perfectly legal and work anyway, and those ones lose to a number the shop is already obliged to print: the price per litre, per kilo or per metre, in the small type under the big one. Least-read number in the building.

Which of these tricks are already illegal in the EU?

The people who build these have a word for them, which tells you it’s a job rather than an accident: dark patterns, interface design that nudges you somewhere you didn’t mean to go.

1. How can you tell if a discount is fake?

You can check half of it on the spot. The tag has to state a prior price, so a “50% off” with no before-price at all is a failure you can photograph standing in front of it. Whether the before-price it does show is true is the other half.

Standing at a shelf tag you have no way to see what that shop was charging a month ago, which is the comparison the rule turns on. On a big marketplace listing you sometimes can: a third-party price-history add-on may have logged the old prices, if one covers that site. Everywhere else the capture that settles it is one taken before the sale started, on something you expected to go on offer, whether a photo of the shelf edge or a screenshot of the listing. Evidence is the only part of your report your national consumer authority can act on.

A struck-through figure is a statement of fact, and it can be wrong like any other. A “was €59.99” that was €59.99 for four days in July, in a shop nobody visits in July, is a graphic design decision. On why the crossed-out number lands so hard, see the biases that quietly cost you money.

The 30-day rule covers goods, so it misses a hotel or a flight. Countries can write their own version for some categories. Food that goes off quickly is the obvious one, so check what your own country did before you lean on it. And it binds the trader without entitling you to the old price.

A sale that deepens without a break, 10% then 20% then 30%, can hold its opening before-price all the way down, in the countries that took up that option ↗ (opens in new tab). A run of separate Sunday sales is not that. Each of those measures against the past 30 days, previous promotion prices included. A tied offer, 3 for 2 or 30% off when you buy three, has no before-price to measure against: it sits outside this rule ↗ (opens in new tab), under the unfair-practices rules instead.

2. Is drip pricing illegal in the EU?

Hiding extra fees until the end of the process is, in the European Commission’s own words, one of the “illegal practices under EU consumer law” ↗ (opens in new tab). The Commission found 10% of the 314 traders it checked doing exactly that.

Drip pricing delivers the total in instalments: one number to get you in, then service and booking fees arriving screen by screen. It’s the one on this list almost nobody can name.

The price on display has to include VAT. Every other charge has to be in front of you before you’re bound. And a charge that was never in front of you at all is one you do not bear ↗ (opens in new tab). That right covers online and doorstep buying only. It does not follow you to a till in a shop.

Airlines sit almost entirely outside those shop rules, so that right does not reach a ticket either. They have a stricter rule of their own: the all-in fare must be shown at all times ↗ (opens in new tab), with optional extras offered opt-in at the start of the booking.

On one Irish booking flow a €15.99 headline fare met a bundle upsell at step two of five, cheapest option €24.23, more than the fare. Nothing there was added by default. You have to choose it and add it yourself, which is the opt-in half of that rule working, so the objection is the size of the step. The published fee list ↗ (opens in new tab) also carries a €20 government tax refund administration fee, which is a charge for asking for your own money back.

Fares observed on ryanair.com/ie/en on 5 September 2026 for a Dublin to Barcelona one-way on 15 October 2026. The €20 fee is from the same airline’s published fees table, checked 6 September 2026, and is charged per passenger rather than per route. Example only, not an endorsement and not advice. Airline pricing changes constantly, so check current prices before acting.

3. The box that was already ticked

Before you’re bound to anything, a trader has to get your express consent to any extra payment. Express meaning you said yes, not that you failed to say no. If they took it from a pre-selected default you’d have had to untick, you are entitled to your money back ↗ (opens in new tab). You need no regulator and no form for this one.

You ask, in these words if you like: I never agreed to this charge. It was added by an option that was already ticked, and I would have had to untick it to avoid it. Please refund it.

If they say no, a certified dispute body in your country can take it up, provided the trader agrees to be there.

That one applies everywhere, physical shops included, which gives a result nobody expects. The undisclosed-charge remedy above stops at the shop door. This one walks in with you. Everywhere means retail, not every contract you sign: your landlord, a betting site and a healthcare provider sit outside it, and your bank only partly.

Of the 314 traders, 36% tried to add optional items to baskets and four in ten of those did it without clearly asking for consent. Adding an optional item is legal. Adding it without asking is the breach.

4. The deadline that never arrives

EU law keeps a short list of practices banned outright ↗ (opens in new tab), with no case-by-case argument allowed. Falsely claiming that something will “only be available for a very limited time”, to rush your decision, is on it. So is claiming to be about to cease trading or move premises when you are not.

The second has a physical form you’ve walked past. It’s the closing down sale that’s been closing down since 2023. Same stock, same window, and a banner that has now faded. That shop is running a practice banned in all circumstances across the EU.

The ban turns on the claim being false and made to hurry you. A real sale with a real end date is fine. A timer that resets when you reload is not. Pressure-selling techniques like countdown timers and scarcity claims turned up in 18% of the 314 traders, and over half of those cases appeared misleading.

5. Is a fake “only two left” counter banned in the same way?

Yes. Same entry as the countdown clock.

No entry on that list spells out a stock counter. The one about false urgency is written about time, which reads like a gap the counter falls through. The Commission doesn’t read it that way. Its guidance on how that list is meant to be applied ↗ (opens in new tab) gives two examples of that entry, and they are fake timers and limited stock claims on websites. Not in the wording, then, and covered all the same.

The lie is the whole of it, not the number. A shop that really has two left may say so. A shop that hasn’t may not. The counter still reading two after you’ve bought one is the version you can screenshot.

On the Commission’s reading, the lying counter and the lying clock sit side by side on the banned-outright list, as they do on the product page. Report either.

Europe’s consumer organisations draw the same line, then add the harder half: proving the dark pattern was there at all.

“It may be simple to prove some obviously unfair design features by taking screenshots. But how are consumers supposed to know, let alone prove, that a business indicated high demand for a product or service to create a false sense of urgency for instance?”

BEUC, The European Consumer Organisation, Towards the Digital Fairness Act ↗ (opens in new tab), December 2025

Which pricing tricks are legal, and work on you anyway?

Nothing in the rules above touches the last two.

6. The 99 on the end

We read prices left to right and stop early ↗ (opens in new tab), so €2.99 files itself nearer €2 than €3. Retailers call this charm pricing. Across 291 price labels on one discount chain’s four national homepages on 3 September 2026, 142 ended in 99 or 95 cents, which is the same trick either way. Just short of half. Exactly one of the 291 ended in a round zero.

In the study the effect sat in the leading digit, not the ending: €2.99 against €3.00 does something, €2.79 against €2.80 almost nothing. Our own European count tells you what shops print, not what the printing does to you. Rounding up in your head changes which prices reach you. It does not take you out of range.

7. The option nobody is meant to pick

Three tiers, and the top one is priced so that nobody sane buys it. That’s decoy pricing, and most people read the top tier as aimed at customers with more money. Its actual job is to make the middle option look like the sensible grown-up choice.

It works, and it works small. Across 3.6 million real wine purchases ↗ (opens in new tab) at one UK grocery chain, the decoys moved what people picked by roughly 1%. The authors then ran the money: at a shift of 1 to 2%, the wines they looked at could earn the chain about £19,000 more over three months. Cents to you. The menu is not what empties the account. The more expensive question is why buying things you do not need feels good.

The unit price, which they are legally required to print anyway

You get one number on the shelf that does the comparing for you. Alongside the selling price, EU law requires shops to show the unit price ↗ (opens in new tab) per kilo, per litre or per metre. That extends to any advert that quotes a selling price, so online listings count too. It’s arithmetic, printed by the shop at the shop’s expense, and almost nobody looks at it. So look at it: the small number under the big one is the one that compares.

Same brand, same drink, same shop, same day, using the retailer’s own displayed unit prices:

Unit prices as displayed by Continente on continente.pt on 5 September 2026. Example only, not an endorsement and not advice. Supermarket prices and promotions change weekly, so check current prices before acting.

The small multipack costs 3.6 times the per-litre price of the 1.75 litre bottle, and the ten-pack, which looks like bulk, costs more than twice it. Both lines on promotion that day were the best value per litre in the range, on discounts of 6% and 20%. A fifth off, against a pack-format gap of 3.6 times.

Nobody is lying to you about the per-litre numbers. Pack format quietly beats promotion, and the shop printed the number that proves it because the law gives it no choice.

It can go missing exactly where you need it most. Ireland’s consumer authority took a supermarket to court over precisely that: “Tesco broke the law by failing to include unit pricing on Tesco Clubcard promotional shelf-edge labels” ↗ (opens in new tab). Tesco Ireland pleaded guilty in 2024 to two sample counts, and was ordered to pay the regulator’s costs and €1,000 to charity. In 2026 the same authority issued Mr Price six fixed payment notices ↗ (opens in new tab) for missing unit prices in two of its shops. Both promoted lines in the table above carried one, so check rather than assume: a 3 for 2 with no unit price defeats the whole move.

The unit is also only as good as the unit chosen. Take a toilet roll pack in Continente, at half price, €19.99 down to €9.99. It still cost about two and a half times the per-roll price of the plain pack beside it. Its 18 rolls, it says, equal 54 rolls.

And it isn’t everywhere. Countries can drop it for services and for auctions, or wherever a unit price wouldn’t help, and on non-food they can cut it back to a list of categories they choose to keep.

Where it is printed, it is still the fastest sum you have. Find the small number and compare the small numbers. The big ones can argue among themselves.

Where do these rules stop?

In a shop you get the discount rule, the unit price and your money back, and not a great deal else: countries can skip even the basic in-store information rule for everyday purchases. On price information, the website you distrust protects you better than the shop you like.

Between them the undisclosed-charge right (drip pricing, the charge you were never shown) and the money-back right (the box that was already ticked) cover the retailer, and the airline only in part. Since June 2026 that same partial cover reaches your money: the money-back right applies to a bank, an insurer or an investment provider ↗ (opens in new tab), and the undisclosed-charge right does not.

What decides it is where you signed up, and when. For a flight the money-back right applies however you bought the ticket. For a financial product it is narrower on both counts: you had to sign up at a distance, and the cover attaches to the sign-up itself. That financial-product half only bites in the countries that have brought the June 2026 change into force.

Open an account or a policy online on or after 19 June 2026, including a new one with a bank you already use, and a pre-ticked box in that sign-up is covered. So is an online bolt-on to an account you already hold, because adding something new to an old agreement is a fresh sign-up in its own right, not just using the account you have. Anything agreed across a branch counter sits outside. Same box, same bank; where and when you signed up decides.

All of that is EU law. If you and the shop are both outside the EU and the EEA, those are not the rules that bind it, so check your own national equivalent before you quote any of them at anybody. Some of it survives the crossing under other names. In the UK the pre-ticked box answers to the Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013 ↗ (opens in new tab), which land in much the same place as the EU rule for ordinary shopping, and in the opposite place for your bank: where what you are mainly buying is a financial service, that rule is switched off. A shop pre-ticking insurance onto a sofa is still caught. For the unit price, look up the Price Marking Order 2004 ↗ (opens in new tab). Northern Ireland has its own Price Marking Order ↗ (opens in new tab).

What can you do when a shop gets it wrong?

Sort it by who can act. Two of the three below need nobody’s permission, because you’re quoting a right written into EU law. The third needs your own country to have decided what you get.

A charge you were never shown before you were committed

You do not bear it. You can say so to the trader yourself, and the right covers online and doorstep buying only.

An extra payment you never actively agreed to

Your money back, and again you ask for it yourself. This one applies everywhere, physical shops included.

A “was” price that never was

Everywhere as well, and here you need somebody else. You can claim if you bought it, and your national consumer authority can act on your evidence. EU law requires your country to give you a way to claim when an unfair practice harms you, which can run to compensation, a price reduction or the contract undone. And what you get and how you claim it are set nationally. Harmed means you bought it. Somebody who spotted the fake and walked away has nothing to claim.

Reporting is a separate move and still worth making, to your national consumer authority. The EU’s own page on unfair commercial practices ↗ (opens in new tab) sets out what counts as one and points on to the consumer bodies country by country.

France publishes the limits of a complaint to its consumer authority ↗ (opens in new tab): the authority decides for itself whether to investigate, and it cannot make the business compensate you. That route is aimed at the practice. The money is a different errand.

Where to take it when the trader says no

Skip the EU’s online dispute resolution platform, shut down on 20 July 2025 ↗ (opens in new tab) whatever older guides still say. If you live in an EU country, Iceland or Norway and the seller was in a different one of those countries, the European Consumer Centres Network ↗ (opens in new tab) can take it up with the trader for you, and the network charges you nothing for it ↗ (opens in new tab).

Otherwise the Commission keeps a list of certified dispute bodies ↗ (opens in new tab) you can filter by country and by sector, financial services included. That’s the desk for a refused refund, though a trader can decline to take part ↗ (opens in new tab) unless your own country makes it compulsory.

Two lists, and only one of them is yours

Forty traders in every hundred had the discount rules right. That isn’t a failure of your concentration, and nothing you do at the till repairs it. Where there’s a rule, it’s somebody else’s to follow, and you can hold them to it: photograph the shelf edge or screenshot the page, then send it to your national consumer authority ↗ (opens in new tab). Where there isn’t, the job is yours. The 99 loses to the unit price, which is already on the shelf, on the lines where the shop bothered to put it. And the middle option stops working the moment you price it against what you came in for, rather than against the tier above it. The Commission used an AI tool to catch the rest of this. You get a label.