The wine added £142 million to the grocery sector in the year to July 18, the company reported, and sales now total £338 million.
Meanwhile Champagne sales practically flatlined with just 1.2% growth and cava sales dropped 11%.
Toby Magill, head of beer, wine and spirits insights at IRI, told OLN: “Prosecco is getting more space and focus in-store because it works so well on promotion. As it gets more popular retailers put more effort and you can see the reverse happening with cava.
“How it develops in the long term depends on how much space Prosecco gets in supermarket range reductions.
“Prosecco is doing well at a crucial time. [Supermarkets are cutting sparkling wine ranges], and if cava bears the brunt of that and Prosecco comes out with more space then it will start riding the crest of the recovery in the next year or so, with more space, fewer rivals on shelf and an increased customer base.”
IRI found that the top two Champagne brands in the market, Moët and Lanson, had had a good year – but that shoppers were turning away from the fizz at the cheaper end of the market.
Magill said: “Champagne brands will need to focus on helping shoppers see the value of their premium brands if they want to fend off the advances of their popular Prosecco cousins as they move into the premium end of the sparkling wine category.”
He said deep discounts on Champagne are driving value out of the category.
“Deep discounts on what is effectively a premium sector in the long term can damage brand equity,” he warned.
Overall sparkling wine sales in the UK off-trade grew 29% to £585 million and volumes grew 28% to 68 million litres.