The Resolution Foundation think tank said 19% of workers aged 18-24 and 22% of ethnic minority staff had lost their job after being furloughed, compared with 9% of employees overall.
The study was based on a survey of 6,000 people conducted in late September, carried out by polling company YouGov.
Job losses were most common in the hospitality and leisure sectors, and for those whose work was already insecure before the crisis - categories in which younger and non-white workers more commonly find themselves in Britain.
Race on its own did not seem to be a big factor but age did appear to play a partial role, with younger workers more likely to leave employment even after adjusting for some other factors.
"Worryingly, fewer than half of those who have lost their jobs during the pandemic have been able to find work since," Resolution Foundation analyst Kathleen Henehan said.
"This suggests that even if the public health crisis recedes in a few months' time, Britain's jobs crisis will be with us for far longer."
Few job seekers applied for roles outside the sectors where they had previously worked, due to a lack of other experience, raising the risk of long-term unemployment.
Some 9 million jobs - around a third of those in the private sector - were furloughed at the peak of the pandemic, with employees receiving 80% of their normal pay.
Slightly over 2 million jobs remain partly or fully furloughed.
Britain's unemployment rate stood at 4.5% in the three months to August, according to official data. The Resolution Foundation estimated the jobless rate in September was around 7%, rising to 20% for those aged 18-24.
(Reporting by David Milliken; Editing by William Schomberg)
By David Milliken
