Just 15 people tested positive for coronavirus among nearly 60,000 who attended trials of mass gatherings including the FA Cup final and the Brit Awards, official figures show.
Nine large-scale events were staged as part of the government's plan to allow for the return of big crowds this summer.
Those who attended were exempt from certain coronavirus rules, such as the rule-of-six.
The government confirmed to Sky News that 15 COVID cases had been recorded out of nearly 60,000 people who attended the events, which "is in line with the broader population".
Latest figures show the rate of people testing positive for COVID in the UK is 22 infections per 100,000 people.
The pilot events included three football matches at Wembley Stadium – the FA Cup final which was attended by 21,000 supporters, an FA Cup semi-final and the Carabao Cup final.
The Brit Awards, which hosted 4,000 people at London's 02 Arena, and the snooker world championships at Sheffield's Crucible Theatre were also involved.
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Several mass gatherings were staged in Liverpool including a rave attended by 3,000 clubbers, a music festival, an outdoor cinema and an indoor business event.
At the Circus nightclub event in Liverpool, partygoers did not have to socially distance or wear face coverings.
People who attended the trial events had to produce a negative lateral flow result from that day or the day before in order to gain entry.
They were also asked take PCR tests at home, before and after they attended the events.
The government has not revealed which trial events were attended by the 15 people who contracted COVID, or whether they tested positive before the events or afterwards.
Evidence from the Events Research Programme will be used by the government to shape its policy for the return of crowds to venues including theatres, cinemas and nightclubs.
Downing Street has said it was "still too early" to determine whether the Indian strain of coronavirus could delay the plan to lift restrictions in England on 21 June.
Cases of the Indian variant in the UK have risen by more than 2,000 in a week, according to official figures.
While most cases were concentrated in the North West – particularly Bolton – and London, Public Health England has said it was seeing "clusters of cases" across the country.
A government spokesman said: "The aim of our world-leading Events Research Programme is to examine the risk of COVID-19 transmission at large events and explore how crowds can be welcomed back in bigger numbers safely.
"The pilots have been designed in a scientifically controlled way to reduce the risk of transmission for attendees. We are working closely with NHS Test and Trace to ensure everyone can be traced following a positive test."