Greater Montreal Area public transit riders will now be able to recharge their Opus cards online.

A number of transit agencies are involved in the roll out of Opus en ligne, a service whereby Opus cards can be recharged using a device that connects to computers via a USB cable.

But there’s a slight catch: the reader costs about $17 tax in, and the fares must be purchased with a Mastercard or Visa.

"Because it has costs, we decided that it shouldn't be payed by all the customers of the transit society," said STM Chairman Philippe Schnobb. "So those who want to use it will have to pay a small amount, and the amount covers everything, we're not making a penny on that."

The development of the online payment system cost $7.6 million, with funding coming from the federal and provincial governments, as well as the participating transit authorities.

The machine "writes" the tickets onto the Opus card, meaning the tickets can be used right after the transaction goes through.

STM riders will only be able to purchase full fare and reduced fare weekly and monthly passes through the online service at first.

Longueuil transit users can buy all kinds of fares with the reader. Other transit agencies are offering the most popular fare options in the online service. TRAM and TRAIN fares will be avaiable, as well as other AMT fares and Laval transit fares.

The Opus readers can be bought online. Shipping is included in the price.