One midlands hospital recorded zero people on trolleys.
12,132 people went without a bed in hospitals nationwide this month.
University Hospital Limerick was the worst-affected by overcrowding, with over 2,000 patients on trolleys.
Midland Regional Hospital Mullingar had the highest figures in the region for this month with 110 people on trolleys. That's followed by 64 in Portlaoise.
In Tullamore, no patients were recorded as waiting for a bed in January.
The Irish Nurses' and Midwives' Organisation says the "provision of safe care is compromised" at hospitals around the country.
It wants the HSE to agree on a realistic workforce plan, which provides for sufficient staff to be employed to provide safe care.