United Airlines announcing it would terminate the employment of any staff who refused to get a vaccination has seen almost all of them get the COVID-19 jab.
Of the airline's more than 67,000 employees, only 320 have not been vaccinated.
"Our vaccine policy continues to prove requirements work - in less than 48 hours, the number of unvaccinated employees who began the process of being separated from the company has been cut almost in half, dropping from 593 to 320," United said in a statement.
"That means 99.5 percent of United's US employees have now chosen to get vaccinated, excluding those who sought an exemption."
The exemption the airline refers to involves some staff who are taking legal action against it for attempting to force them to be vaccinated despite their religious beliefs.
United had set a deadline of September 27 for staff to be vaccinated, if they failed to comply, their employment would be terminated by the airline.