Staff working at the site in Motherwell, run by the private outsourcing firm Sitel, were told to work from home on Sunday after NHS officials became aware of “potentially linked cases” of the novel disease.
An NHS Test and Trace spokesperson said all employees working at the Lanarkshire call centre would be offered a coronavirus test within the next 24 hours.
“We are aware of a local outbreak of Covid-19 at the Sitel site in Motherwell,” the spokesperson said.
“This is being managed by Sitel and colleagues in NHS Lanarkshire, who are following appropriate test and protect action in line with Scottish government advice.
“We take the safety and wellbeing of our staff very seriously. Everyone at the site is currently working from home while a deep clean takes place, and will be offered a test within the next 24 hours.”
NHS Test and Trace is a service operated by the NHS in England to track and help prevent the spread of Covid-19 south of the border.
Dr David Cromie, NHS Lanarkshire consultant in public health medicine, said: “We became aware this morning of a number of potentially linked cases of coronavirus in Lanarkshire.
“We instigated some immediate measures to reduce risk and are currently investigating the situation.”
It came after Scotland recorded 23 new confirmed cases of coronavirus – the highest increase in almost a month.
Three of these were in the Lanarkshire health board area.
This figure has now risen in each of the last five days – up from three on Tuesday – although no further deaths have been recorded.
It is the highest record for new cases since 21 June, when there were 26 positive test results.
Scotland’s national clinical director, Jason Leitch, said he would not be concerned with fluctuating figures.
He told BBC Scotland on Saturday, when there was a recorded spike of 21 new cases: “I expect day-to-day variation and the next thing I look at is the spread around the country.
“So 21 in one small town would worry me much more than 21 spread around the country – and these 21 are spread around the country.”
Additional reporting by Press Association