Thousands of primary and secondary school students are still waiting for their annual bus tickets due to a technical glitch.

Bus Éireann is to email temporary tickets to families which can be used this week as many return to school.

Alternatively for those who do not receive a temporary ticket by email “evidence of payment will be accepted for the opening days of the new school year”, the company said in a statement.

Tickets cost between €100 for a primary school pupil to €650 per family. So far this year the company has yet to issue 31,500 of the 115,000 tickets purchased.

In the past such tickets were issued through regional transport offices but this year all tickets had to be bought online.

Among the technical glitches in the new online payment system introduced this year were the type of web browser used by customers or if it needed upgrading. The website requires users to have Chrome. Firefox, Safari or Internet Explorer version nine or higher, the company statement said.

Nicola Cooke of Bus Éireann said the system had been tested beforehand. However some of the issues were "down to customer behaviour and customer interfacing with the system. We couldn't predict what consumer behaviour was going to be," she said.

For a short period it "wasn't possible to input medical card details", Nicola Cooke of Bus Éireann told RTÉ Radio. However she said the issued had been "worked through" and had "all been rectified".

She urged parents not to be “unduly concerned” as there will be “nobody that can’t get on a bus that has paid by August 1st”, which was the extended deadline for on time applications. Children could turn up at buses with their receipt or email confirmation, she said.

There were also some 18,000 late payments whose tickets were “a little bit down the line” but these consumers must bear the “shared responsibility”, she said.

Customers with concerns are urged to contact Bus Éireann’s freephone helpline 1800 -945945.