One in five Local Link evening bus services had fewer than ten passengers a week on average last year.
Another 20% were cancelled or didn't start running as planned.
The route with the lowest take-up was number 115c between Ballivor and Navan in County Meath, according to the Sunday Times.
It had just 215 passengers across all of 2019.
The busiest scheduled service was the number 363 between Tallow and Dungarvan in Waterford which averaged 99 passengers a week.
Next after that is the bus between Wexford and Rosslare Harbour followed by the service from Newbridge to Athy in Kildare.
The NTA has noticed that some of the routes that have higher commuter numbers have departures that run later into the night than others which aren't so popular.
It says many of the routes have needed some months to gain traction in the local community and prove themselves as a reliable transport service.
Reporting by Tom Douglas
