What a Countdown Timer Adds to a Sale
A countdown timer usually sits beside a discount, and its deadline may not be real. The one controlled test of a timer found the markdown doing the work, a genuine deadline can shift purchasing, and many of the timers anyone has counted were false.
Answer to the question
Do countdown timers make people buy?
The evidence on the timer itself is thin. In a 2022 experiment with 245 people, a markdown raised choice of the discounted chair from 17 to 56 per cent and a countdown timer added nothing the study could detect. Real deadlines can shift purchasing, as coupon expiry dates do, but about two in five countdown timers counted in a 2019 crawl of shopping sites were deceptive.
Key takeaways
- In Jelmer Tiemessen's 2022 experiment with 245 people, a markdown raised choice of the grey chair from 17 to 56 per cent, and adding a countdown timer left it at 46 per cent, no gain the study could detect.
- Nobody in that timer group named the timer as a reason for choosing, and five said they avoided the offer because it looked fake.
- Jeffrey Inman and Leigh McAlister found in 1994 that coupon redemptions rose again just before a real expiry date, so a true deadline can move purchasing.
- Arunesh Mathur's 2019 crawl of about 11,000 shopping sites found that 157 of 393 countdown timers were deceptive: they reset, or the offer outlasted them.
- The European Commission's 2023 sweep found fake countdown timers on 42 of 399 online shops, and EU law lists falsely claiming limited availability as unfair in all circumstances.
A trade book says a countdown timer raised purchasing, and the whole case is one founder's interview, with no method and no baseline. That is Mindy Weinstein's The Power of Scarcity, and it is the strongest claim for the timer in print. The peer-reviewed work is thinner, and it has to be split in two, because a timer sits beside an offer and its deadline is either real or it is not.
The markdown did the work, not the timer
Jelmer Tiemessen, then a master's student at Radboud University in the Netherlands, tested a countdown timer against the offer it usually travels with. His 2022 thesis became a short paper in 2023, written with his two supervisors. He recruited 245 people through the research platform Prolific and asked each to pick an office chair from a fictional webshop, within a work budget.
Both chairs cost $260. In one group they differed only in colour. In a second, the grey chair also showed an original price of $320, so it looked like a $60 saving. In a third it showed the same markdown plus a banner reading "Offer expires in", with seven minutes on the clock. The clock restarted whenever the page was refreshed.
| Group | People | Chose the grey chair |
|---|---|---|
| No offer | 75 | 17 per cent |
| Markdown only | 91 | 56 per cent |
| Markdown and timer | 79 | 46 per cent |
The markdown moved people, and the timer added nothing the study could detect. Colour mattered too: with no offer on, more than four in five chose the black chair, and colour was the reason people gave most often. The timer group picked the grey chair a little less often than the markdown group, a gap the study could not tell from chance. Asked for their reasons, nobody in the timer group mentioned the timer. Ten people in the markdown group said a chair on sale must be worth more, a reading of the markdown that does not depend on any deadline.
Five in the timer group said they had avoided the offer because it looked fake.
Among those who chose the grey chair, reported fear of missing out was higher in the timer group than in the group that saw no offer, though the markdown group sat between the two and could not be told apart from either.
The authors read this as the markdown doing the work. The money was imaginary, the product was one chair, the timer was false by design and the study was exploratory. It tells us about a deceptive timer in a lab, which is narrower than timers in shops.
A real deadline has a mixed record
If a false clock adds nothing detectable, the next thing to ask is whether a true deadline does. The older evidence says it can. Jeffrey Inman and Leigh McAlister, then at the universities of Wisconsin-Madison and Texas at Austin respectively, reasoned in 1994, from regret theory, that a coupon's expiry date would produce a second burst of redemptions just before it passed.
They checked weekly redemption records for spaghetti sauce coupons in two cities, taken from Nielsen consumer panels, and the results were consistent with the prediction, an expiration effect in their phrase. The usual assumption had been a peak after the coupon dropped and a steady decline.
The deadline was real and the behaviour was purchasing, with no timer on any screen.
The data are more than thirty years old and cover one product. They show a pattern and not the size of any gain to a seller.
Stated intentions give a flatter picture. A 2022 experiment led by Peter Broeder showed 208 Europeans a web-shop offer marked either "limited-time" or "in stock". The limited-time notice did not on its own raise their intention to buy. It raised perceived scarcity, which raised a sense of competing with other buyers, which raised intention, but only among the Italian participants and not the Dutch ones. We could reach only the abstracts of this paper and of the 1994 coupon study.
A 2022 meta-analysis pooled 416 effects from 131 studies of three kinds of scarcity cue, limited supply, limited time and demand. Cues of all three raised stated purchase intention by a modest amount, none was reliably ahead of the others, and the outcome was intention in a scenario, not a purchase. The comparison is set out in Which Kind of Scarcity Works on You.
Many shops run timers that reset
Suppose the advice works. Then every seller has a reason to run a countdown timer whether or not the deadline is real, since a true deadline costs a sale when it passes and a false one does not. Two counts show what sellers do.
A 2019 crawl of about 11,000 shopping sites, led by Arunesh Mathur, found 393 countdown timers. The crawl separated countdown timers from limited-time messages, which say a sale will end soon without giving a deadline. The team revisited pages over time and defined a deceptive countdown timer as one that reset with the offer still on, or whose offer outlasted it. By that definition 157 of the 393 were deceptive, on 140 sites. A smaller hand-built sample of 60 timers in the Radboud thesis found 27 judged deceptive, 22 of them with deadlines under 24 hours. Researchers class such timers as dark patterns, designs that steer a user toward a choice they might not otherwise make.
Of 399 online shops screened in 2023 by the European Commission and consumer authorities from 23 member states, Norway and Iceland, 42 used fake countdown timers, with deadlines to buy specific products. The two counts use different methods and measure different things, so they cannot be laid side by side, and neither asked sellers why.
The law in the EU already speaks to this. The Unfair Commercial Practices Directive of 2005 lists, among practices unfair in all circumstances, falsely stating that a product will be available only for a very limited time in order to elicit an immediate decision.
For a seller the implication is to hold a timer to its word: show a deadline, keep it, and do not extend it for the next visitor. No study here tested an honest timer, so that is our suggestion. A shopper can run a rough version of the researchers' test by reloading the page, since a clock that restarts is not counting down to anything.
A caught timer may cost more than it earns
If the countdown timer does sell more, the price is paid in what shoppers learn from it. The Radboud experiment asked all 245 participants whether countdown timers influence them. Ninety-three said yes, 38 said sometimes and 108 said no. Several of the no answers gave distrust as the reason, one calling the timer "a cue for the seller to be not honest".
Self-reports of being unmoved are weak evidence, but the direction matches the persuasion knowledge model of 1994, under which people who recognise a tactic as a persuasion attempt tend to discount it. It also matches reactance, the resistance people show when they feel their freedom to choose is under pressure, taken up in Reactance: Why a No Makes You Want It.
Whether an honest timer on a true offer adds anything the markdown does not, and whether a shopper who has met a resetting clock discounts the honest one too, are untested here, and whether the seller who runs a false one comes out ahead after a year, once the shoppers who learned to distrust it are counted, is what the Radboud test, the coupon panels and the intention studies cannot say.
Common questions
Do countdown timers actually make people buy?
The evidence on timers themselves is thin. In a 2022 experiment with 245 people, a markdown raised choice of the discounted chair from 17 to 56 per cent, and adding a countdown timer did not raise it further. A real deadline can change behaviour: coupon redemptions rose just before expiry in a 1994 study.
Are fake countdown timers illegal?
In the EU, the Unfair Commercial Practices Directive lists, among practices unfair in all circumstances, falsely stating that a product will be available only for a very limited time in order to elicit an immediate decision. The European Commission's 2023 sweep found fake countdown timers on 42 of 399 online shops. This describes the text and is not legal advice, and other jurisdictions differ.
How can you tell whether a countdown timer is fake?
Reload the page. A timer that restarts, or an offer that is still available after the clock reaches zero, is the pattern Mathur and colleagues counted as deceptive in 2019. They found those cases by revisiting pages over time. Reloading is our simplified version of that check.
Sources
Tiemessen, J., Schraffenberger, H., & Acar, G. (2023). 'The Time is Ticking: The Effect of Limited Time Discounts on Consumers' Buying Behavior and Experience.' Extended Abstracts of the 2023 CHI Conference on Human Factors in Computing Systems, 1-11. doi:10.1145/3544549.3585735
Tiemessen, J. H. (2022). 'The Time is Ticking: The Effect of Deceptive Countdown Timers on Consumers' Buying Behavior and Experience.' MSc thesis, Radboud University.
Inman, J. J., & McAlister, L. (1994). 'Do Coupon Expiration Dates Affect Consumer Behavior?' Journal of Marketing Research, 31(3), 423-428. doi:10.1177/002224379403100310
Broeder, P., & Wentink, E. (2022). 'Limited-time scarcity and competitive arousal in E-commerce.' The International Review of Retail, Distribution and Consumer Research, 32(5), 549-567. doi:10.1080/09593969.2022.2098360
Barton, B., Zlatevska, N., & Oppewal, H. (2022). 'Scarcity tactics in marketing: a meta-analysis of product scarcity effects on consumer purchase intentions.' Journal of Retailing, 98(4), 741-758. doi:10.1016/j.jretai.2022.06.003
Mathur, A., Acar, G., Friedman, M. J., Lucherini, E., Mayer, J., Chetty, M., & Narayanan, A. (2019). 'Dark Patterns at Scale: Findings from a Crawl of 11K Shopping Websites.' Proceedings of the ACM on Human-Computer Interaction, 3(CSCW), Article 81. doi:10.1145/3359183
European Commission (2023). 'Consumer protection: manipulative online practices found on 148 out of 399 online shops screened.' Press release IP/23/418, Brussels, 30 January 2023.
Directive 2005/29/EC of the European Parliament and of the Council of 11 May 2005 concerning unfair business-to-consumer commercial practices (Unfair Commercial Practices Directive), Annex I, point 7.
Friestad, M., & Wright, P. (1994). 'The Persuasion Knowledge Model: How People Cope with Persuasion Attempts.' Journal of Consumer Research, 21(1), 1-31. doi:10.1086/209380
Weinstein, M. (2023). The Power of Scarcity: Leveraging Urgency and Demand to Influence Customer Decisions. New York: McGraw Hill.