Spanish unions have called on the maximum number of people to support Wednesday's general strike.
The strike, the second of the year after the stoppage on March 29, is in protest at the social and economic policy of Mariano Rajoy's government and his right-wing Popular Party.
It will coincide with strikes in Portugal and Greece and a day of protest at austerity policies throughout Europe.
The unions will respect minimum service agreement and 35 percent of local trains will run during peak hours and 30 percent during the rest of the day.
Long-distance trains will run at 25-percent service and public transport services will be at around 30 percent. International flights will be greatly affected with only 25-percent service to be provided at airports.
"A huge participation will make it more than a general strike. We want to make it a day of general participation of the people," said Candido Mendez, leader of the Union General de Trabajadores (UGT) in the El Pais newspaper.
"We want it to be an act of democratic affirmation and it would be good if the government considers the strike as a guarantee to oppose cutbacks in Brussels," he added.
Ignacio Fernandez Toxo, leader of Comisiones Obreras (CC.OO), also highlighted the importance of the demonstrations which will take place in cities throughout Spain in the late afternoon.
"We hope for a huge response in the workplace, but also for the demonstrations, because there are many people who want to, but are unable to go on strike, such as unemployed people and pensioners," he said.
"I think this is going to be a strike that is more visible and people will see the anger in the demonstrations," said the union leader.
"This is a move for a social model in which we should sign a European social pact and force the institutions to change direction and start talking about growth and employment," added Toxo.