There were 6,335 new Covid-19 cases and 37 more fatalities recorded during the previous 24 hours, the Public Health Ministry announced on Thursday morning.
The number of new cases rose from 5,857 announced on Wednesday, when the country recorded 55 more deaths.
On Wednesday, 7,218 Covid-19 patients were discharged from hospitals after recovering from the coronavirus.
Since April 1, when the third wave of Covid-19 began, Thailand has treated 2,059,464 Covid-19 patients, 1,959,663 of whom have recovered to date.
Since the pandemic started early last year, there have been 2,088,327 Covid-19 cases, with 1,987,089 complete recoveries so far.
The death toll stood at 20,487 during the third wave and 20,581 since the beginning of the pandemic.