Meanwhile, Portlaoise is the cleanest town in the country.
Dumping of large items along the canal in Mullingar is being pinpointed as a reason for it failing to attain a European standard for cleanliness.
The Bring Centre at the Council Buildings was also adjudged to be in a poor state.
The results come from the latest Irish Business Against Litter survey which ranked the town 25th out of 40 looked at by An Taisce.
Portlaoise is the cleanest town in the country.
Athlone and Tullamore have retained their status as cleaner than European norms - ranking 12th and 15th respectively.
IBAL’s Conor Horgan says to won't take much for Mullingar to shoot up the list:
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