The Belgian rail company is running eight extra services.
The rail company is marketing a special reduced ticket for people who want to come to Brussels.
The Brussels local transport company MIVB too will be hit by stoppages as workers walk out to take part in the demo, but the socialist union at the MIVB insists that trams, buses and the metro will be operating to a degree on Thursday.
Trades unionist Dario Coppens: "It's hard to make a forecast, but I'm anticipating that 60 percent of metros, 50 percent of trams and 40 percent of buses will operate."
Mr Coppens, who speaks on behalf of all the unions at the MIVB, believes people will be able to get to work by public transport.
Like at many companies trades unionists at the MIVB will take part in the demonstration, but places of work will not be picketed.
There will not be any pickets at MIVB bus stations or tram depots and MIVB staff will ensure a service.
Flandersnews.be / Expatica