Expansion means Frankfurt can now test more than 10,000 passengers a day, with 97% of results having been received within 24 hours in August. The facility is run with commercial partner Centogene and was launched in June.
On average, only 1% of samples taken have tested positive during the last six weeks.
Lufthansa said: “Passengers who registered in advance waited approximately 20 minutes before being tested. The majority of these passengers were travelling from Spain, followed by the USA, Turkey and Croatia.
“Approximately 50,000 of these passengers were tested before departure to countries including China and Dubai where a negative test result is mandatory for entry.
“The general population from the wider Frankfurt region have also been encouraged to use the test centre and since mid-August, an additional test centre has also opened at Hamburg Airport.”
On average, approximately 4,500 tests per day were carried out at Frankfurt during July and August, with expansion meaning capacity has more than doubled.
Lufthansa said this was currently “more than sufficient during times of high demand”. Special fast lanes are available for Lufthansa Group status customers, business and first class travellers.
"It is correct that the testing strategy for travellers from high-risk countries will be maintained in September," said Christina Foerster, Lufthansa Group customer, IT and corporate responsibility board member.
"Instead of abolishing the tests from October and dismantling the successfully established testing infrastructure at airports, the existing testing capacities should be further expanded and used even more extensively,”