The food company's television ad, which broadcast earlier this year, showed scenes of people eating food and using the company's app in unusual locations or circumstances.
Viewers were told they could "order what you want; where you want; when you want it".
On screen text stated: "Some restrictions apply, obviously..."
Some 22 people who felt the advert was unfair, as Deliveroo does not cover the whole of the United Kingdom, complained to the Advertising Standards Agency.
Whilst the service covers major population areas, a simple postcode search shows it has coverage omissions; for example outlying areas of Scotland like Kirkwall in Orkney.
Deliveroo acknowledged that there were locations which they do not currently cover but believed the text “some restrictions apply, obviously” made this clear.
The Advertising Standards Authority said consumers were likely to expect that Deliveroo’s service applied throughout the UK without exception "given the absolute nature of the claim".
It then ruled: "Given the expectation set up by the ad, we considered it was not sufficient to make consumers aware they would need to check for availability in their area.
"Because we considered the ad suggested delivery was unrestricted throughout the UK when that was not the case, we concluded that it was likely to mislead."
A Deliveroo spokesperson said: "Deliveroo designed a playful advert to show that, through our service, people are able to order food to a wide range of places, whether home or work, for a range of occasions.
"We know some will be disappointed that their local area isn’t currently served by Deliveroo, but we are expanding rapidly across the UK and will be coming to their town or city soon."