In 165 cases, the turnaround time was over five hours.
Over 64,000 ambulances spent over an hour at a hospital last year, before offloading a patient and getting back on the road.
It represents nearly one in every four ambulances that arrived at hospitals.
Turnaround times involve the interval between an ambulance's arrival at a hospital to when the crew has handed over a patient and is ready to take another call.
The target time is less than 30 minutes.
However, on 64,182 occasions last year, the turnaround time was over an hour.
That's nearly 23 per cent of all ambulances that went to hospitals throughout the country last year.
In 165 cases, the turnaround time was over five hours.
Over 20,000 fewer ambulances had turnaround times of over an hour in 2019 and 2020 as last year.
The HSE says during the Covid pandemic, the National Ambulance Service experienced longer offload delays at emergency departments - due to infection prevention and control measures.
David Hall is chief executive of Lifeline Ambulance Service:

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