However, this happen in less than half of the sample of journeys made for the study, the results of which appear in several daily newspapers including De Standaard and De Morgen.
The Belgian rail company NMBS has dismissed the figures.
Tickets were checked during just 44 percent the 436 journeys made as part of the survey.
Not surprisingly, the longer a passengers is on the train, the more chance he/she has of his/her ticket being checked.
However, even during journeys of longer than an hour; just 57 percent of tickets were checked.
Meanwhile, just a third of those travelling to or from Brussels had their tickets checked.
The Belgian rail company NMBS says that its guards carry out more ticket checks than the survey suggests.
"According to our figures 63 percent of tickets are checked. This is probable due to the sample our data is based on being six times bigger than that used by TreinTramBus. Our figures are based on almost 2,500 journeys spread over 2 months”, the NMBS spokesman Bart Crols told journalists.
However, NMBS believes that there is still remove for improvement and its aim is that “every ticket should be checked.
"There are currently 50 people that carry out ticket checks in small special ticket check teams on trains. We hope to increase the number of special ticket check teams by taking on an extra 15 to 20 people this year", Mr Crols said.
Flandersnews.be / Expatica