The study, by web hosting company 34SP.com, tested public Wi-Fi at 100 commercial premises across northern England – including both independents and chains such as McDonald's, Burger King, Costa, Starbucks, Subway, Pizza Hut, Pizza Express, Zizzi, Wetherspoons and Travelodge.
It found that on average, independents are offering 70 per cent faster download speeds than chains, as well as nine times higher upload speeds.
The best performing premises in the study was independent venue The Bar in South Manchester, which had the fastest download speed (36.11mbps), the fastest upload speed (18.08mbps) and one of the lowest ping speeds (31ms).
The worst performing premises were the Manchester branches of Zizzi and Travelodge, neither of which had a working Wi-Fi connection during the test period.
"Our research suggests that independent restaurants, bars and cafes offer much faster public Wi-Fi speeds than the big chains," said Daniel Foster, co-founder and technical director of 34SP.com.
Although independents are outperforming chains when it comes to download speeds – with an average of 10.99mbps compared to 6.46mbps – public Wi-Fi is still some way behind residential broadband, which has average download speeds of 18.7mbps.
Even mobile networks are offering faster download speeds, with 4G achieving an average of 15.1Mbps.
"Nowadays, the general public is spoilt for choice when it comes to getting online. There are literally millions of wireless networks across the UK in 2015 and consumers are increasingly heading to restaurants, bars and cafes that offer great internet access as well as great food and drink,” said Foster.
“Meanwhile, the slowest public Wi-Fi connections have already been eclipsed by 4G and in some cases even 3G.
"Businesses that fail to offer good Wi-Fi speeds to their customers are missing out financially because these consumers typically spend lots of money on snacks and drinks while they surf. When you consider how little it costs for businesses to set up public Wi-Fi, the investment effectively pays for itself within weeks."