Nottinghamshire County Council and Nottingham City Council said the county-wide community testing programme – testing people without coronavirus symptoms to ensure they are not carrying the virus and potentially transmitting it to others – reached the landmark this week.
Out of the tests, nearly 500 positive cases of Covid-19 were identified.
Jonathan Gribbin, Nottinghamshire director of public health, said: “Asymptomatic testing plays a vital role in detecting these cases and breaking the chain of transmission.
“I’m delighted we’ve reached the 100,000 mark with so many people in Nottinghamshire taking regular tests to protect their communities and loved ones.
“Lateral flow tests are free, quick and easy to do and can be completed twice a week.
Thank you to everyone who has already used these tests.
"With rates in Nottinghamshire remaining at a high level, I encourage everyone to make twice weekly testing a part of their routine, even if they have already been vaccinated.”
The programme has also given out nearly 60,000 home testing kits.
Andy Macey, Nottinghamshire Fire and Rescue Service group manager, said: “The fact the testing programme has gone on to test their 100,000th person is fantastic and a great achievement.
“On behalf of everyone from the service, we want to congratulate and thank everyone on this programme for their hard work throughout the tough months and for stepping up to this challenge.”
The testing sites in Bassetlaw are as follows:
Retford Town Hall – Tuesday to Friday
Old Market Square, Worksop – Thursday to Saturday
Harworth Town Hall – Monday to Wednesday