The HSE has paid private labs almost 250 million euro for Covid-19 testing during the pandemic.
According to freedom of information figures, the bill for January was nearly 36 million euro.
The HSE says at the start of the pandemic, Ireland was reliant on Covid testing within its hospitals, public labs and the National Virus Reference Laboratory.
But due to greater demand, off-shore testing was sourced and this was retained to make sure there wasn't a shortfall.
By January, the HSE had access to testing for 22,000 a day, through state and private providers.
There was also additional off-shore capacity available on demand.
Between March 2020 and April of this year, the HSE paid private labs nearly 250 million euro.
The highest was nearly 36 million in January - during the peak of the pandemic - followed by over 28 million last October.
The HSE says it recognises the role of commercial providers in supporting the Covid response programme - and the value of the additional capacity.