Asda complained after a national TV and press ad for Tesco claimed to offer price comparisons on “real baskets” bought by customers between the two supermarkets.
The watchdog agreed with Asda on three objections and ruled the ad should not appear again in its current form.
It ruled Tesco’s claims about the number of baskets compared, the range of products compared and explanation of its methodology meant the ad was misleading.
However, the ASA rejected five other complaints submitted by the Wal-Mart-owned supermarket against its rival.
Meanwhile, a separate press and outdoor Tesco ad, which compared its prices on washing-up liquid, red wine and nappies with Aldi was also ruled misleading.
The watchdog upheld two complaints submitted by Aldi concerning comparisons claims on products that were not “like for like” at the two supermarkets.
It also agreed that the strapline “Britain’s biggest discounter” could be misinterpreted and was therefore misleading and shouldn’t be used without further clarification.
A spokesman for Tesco said: “We produced our Real Basket adverts in line with the ASA’s own guidance on comparative advertising and in consultation with Clearcast – the company responsible for pre-transmission clearance of all TV adverts. We are reassured that in its investigation of these complaints the ASA has not found anything fundamentally wrong with the substance of our message that more of our customers’ matched baskets are cheaper at Tesco than they would have been at Asda. We welcome the further detailed guidance the ASA has provided on the execution of the adverts as this will make them even clearer for customers going forward.”
Price comparison advertising between supermarkets has become even more aggressive during the recession. The ASA said it would make such advertising a priority for scrutiny this year amid concerns the fight for dwindling consumer spend would lead to an increase in misleading claims.
ASA chairman Lord Chris Smith told Marketing Week that comparison claims are a “valid and sensible form of advertising”, especially in a recession, but that advertisers need to make sure they make a fair comparison”.