The promotion appeared during the checkout process on Amazon.co.uk and encouraged people to sign up for Prime membership.
An Amazon advert has been banned for misleading customers in a bid to encourage them to join its Prime membership scheme.
The Advertising Standards Authority (ASA) upheld seven complaints about the promotion, which appeared during the checkout process on Amazon.co.uk.
It stated: “We’re giving you a 30-day free trial of Amazon Prime! Starting with this order.”
Underneath the text was a gold box asking people to “Order Now With Prime”, which was contained within a larger grey box that read: “Continue with Free One-Day Delivery. Pay later.”
The option to “Continue and don’t gain Amazon Prime benefits” was written in fainter blue writing to the left, which complainants said made the process unclear and misleading.
The ASA also cited issues with the presentation of information regarding payments beyond the trial period, which was contained within small print at the bottom of the page.
It read: “By signing up you acknowledge that you have read and agree to the Amazon Prime Terms and Conditions and authorise us to charge your credit card after your 30-day free trial.”
Explaining its decision, the ASA said: “We considered that the average consumer was likely to view the text within the grey and gold boxes as the only two options available, with the ‘option’ in the grey box allowing them to continue without signing up to Prime, when that was not the case.
“Because we considered that the average consumer was likely to view the text within the grey and gold boxes as the only two options available, with the ‘option’ in the grey box allowing them to continue without signing up to Prime, when that was not the case, we concluded that the presentation of the options was likely to mislead.”
Amazon said it wanted to make sure customers who joined Prime did so intentionally.
The company provided the ASA with data it believed proved customers were clear about what they were doing, but it was dismissed as being undemonstrative that the average consumer would not be misled by the options.
An Amazon spokesman said: “The evidence from millions of transactions demonstrates that customers have had positive experiences.
“The ASA has instead based its ruling on a handful of complaints and a subjective opinion of the page. We will continue our discussions with the ASA.”