The decision comes while advertising code writers CAP and BCAP are reviewing broadband speed and unlimited use claims in advertising, with findings expected by the end of the year.
The TV ad for BT Total Broadband showed an estate agent showing a man round a property while he discussed the house with his partner at home on her PC.
The estate agent attempted to access a webpage but had to wait for the page to reload while the partner loaded the website instantly and then visited different webpages swiftly.
A voiceover stated “BT is rolling out up to 20 meg speeds to give you a consistently faster broadband throughout the day even at peak times” while on-screen text stated “Comparison to BT’s 8Mb service.”
Complainants questioned whether the claim that BT was rolling out up to 20 meg, speeds even at peak times, was misleading and could be substantiated. Broadband rivals BSkyB, Virgin and Talk Talk also challenged aspects of the campaign.
The Advertising Standards Authority ruled that the campaign suggested BT could demonstrate faster speeds “in all instances” and was misleading. It must not appear again in its current form.
Industry regulator Ofcom has previously called for a new ISP code of conduct, which all of the UK’s larger ISPs have agreed to in principle.In July, Ofcom research found that broadband users aren’t receiving the broadband services advertised by ISPs.