Cross-checking of death certificates in New South Wales has revealed more than 300 additional COVID-19 deaths.
Data recorded by the NSW Registry of Births, Deaths and Marriages has revealed an extra 331 COVID-19 related deaths between January 2020 and March 2022.
The death certificates showed a certified doctor had listed coronavirus as "a contributing factor or cause of death".
"To ensure NSW COVID-19 mortality data is as robust as possible, NSW Health has been cross-checking these deaths with all those identified in death certificates," a spokesperson said in a statement.
It means the number of COVID-19 fatalities in NSW since the start of the pandemic is now 2,433.
The data shows 82 per cent, or about 270 people, of the additional deaths, occurred from January this year during the peak of the first Omicron wave.
Another 58 died in 2021, coinciding with the peak of the Delta wave, and three were found to have died in 2020 when the original strain was present.
It comes as the number of deaths reported in recent days has increased.
The state recorded 17 coronavirus-related deaths in the 24 hours to 4pm Wednesday, and 15 for the day before that.
