Motorists left behind nearly €190,000 in unclaimed change on toll roads last year.
However, that extra revenue was exceeded by the volume of unpaid tolls, which came in at €287,000 according to figures from Transport Infrastructure Ireland.
Toll revenue on nine different routes came to €210 million last year with a further €170 million raised from vehicles using Dublin’s M50 motorway.
The M50 was by far the most profitable toll route in Ireland, although a bad debt charge of €5.184 million put a dent in revenue.
The next most lucrative toll was the M1 connecting Dublin to Belfast, where €39 million was paid out by motorists.
That included about €15,000 in overpaid tolls with Transport Infrastructure Ireland saying drivers were able to collect change on the route.
Another €22.6 million was collected on the M3 motorway, which included €48,000 that was overpaid by people using the route.
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A cool €39 million was paid in tolls on the M4, including €30,000 in excess change left behind by motorists.
There was €23.3 million paid on the M7/M8 motorway which branches off to Cork and Limerick, according to Transport Infrastructure Ireland. Overpaid tolls made up €23,000 of that.
Another €18 million was forked out by motorists using the M8 motorway to Cork, with just €8,000 left behind in “excess tolls”.
Transport Infrastructure Ireland said toll revenue on the M6 motorway connecting Dublin and Galway was €11.9 million, with €16,000 over paid.
A further €21.9 million was paid at the Limerick Tunnel, €10.6 million on the Waterford city bypass, and €22.6 million in the Dublin Port Tunnel.
Excess tolls on those three routes came to €47,000.
The figures also showed there was €287,000 in unpaid tolls across the nine routes.
The Transport Infrastructure Ireland figures showed that about 21.5 per cent of tolls are still being paid in cash by motorists.
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Another 17 per cent or so are paid by debit or credit card, just over 60 per cent through an online account, and a tiny fraction of less than 1 per cent were “pre-paid”.
On the M50 motorway – where cash payments are not allowed – 65 per cent were paid through an online account or by tag.
Another 17 per cent of tolls were paid based on video, and 18 per cent were “unregistered” meaning the person had to make arrangements for payment each time they used the road.
On overpaid tolls, Transport Infrastructure Ireland said: “Toll users at [each] plaza were able to receive change from at least one booth/lane per direction on a 24/7 basis.”
