The fight to get a living wage for a McJob is heating up with protests taking place Wednesday in cities across the U.S.

Workers in Boston, New York, Detroit, Chicago and San Francisco were among those who walked the streets, demanding wages of $15 an hour and better working conditions.

Fast food workers in Toronto also walked off the job today to rally for higher pay. Labour groups organized protests at the McDonald's headquarters, the Ontario Ministry of Labour and at Toronto Pearson airport.

The campaign called "Fight for $15" is being spearheaded by the Service Employees International Union and began in late 2012. On Wednesday, organizers say protests for higher pay and union for low-wage workers are planned for more than 230 cities and college campuses.

The protests come two days after a study by the University of California-Berkeley found that the U.S. taxpayer forks out $153 billion a year to support the families of low-wage workers.

That's the cost in food stamps, Medicaid and child care subsidies for families in which at least one worker is holding down a low-wage job.

$15 an hour 

 "I'm here to fight for $15 and a union. We deserve a better wage and working conditions," said Isaiah Mitchell, a 19-year-old cook at a Jack in the Box in San Leandro, Calif.

"It can be dangerous in the kitchen. It's so hot, and there's a lot of rushing to get food to the window. We don't get set hours. It fluctuates each week," he told the Guardian during a protest in San Francisco.

McDonald's has been a focus of some of the protests, with workers picketing outside its outlets in some cities.

The fast food giant promised a wage hike for its workers two weeks ago, but just to $1 an hour above the local minimum wage and only at its wholly owned restaurants. Most of McDonald's restaurants are owned by franchises and its own restaurants make up only 10 per cent of the 14,300 McDonald's in the U.S.

Wages edging up

It's not the only U.S. company promising raises, albeit to about $9 an hour – Walmart, Gap, Marshall's, Burger King and health-care insurer Aetna also have pledged to raise the wages of their poorest workers in the past two months.  

In an emailed statement, McDonald's said it respects the right to "peacefully protest" and that its restaurants will remain open Wednesday. In the past, it said only about 10 to 15 McDonald's Organizers say the measures taken to raise wages are not enough and workers need collective action.

"The voices of Walmart and fast food workers have shown the power of collective action in standing up to corporate greed and a system that for far too long has only benefitted those at the very top," said Richard Trumka, the president of labour federation AFL-CIO.

"Today's actions by tens of thousands of workers significantly advance a raising wages agenda that gives every worker a chance to achieve the American Dream," he said in a statement.

Mary Kay Henry, the SEIU's president, said the push has already helped prompt local governments to consider higher minimum wages, nudged companies to announce pay hikes and made it easier for SEIU members to win better contracts. Those results are inspiring other groups of workers, she said.

"It has defied a sense of hopelessness," she said.

With files from the Associated Press