The workers gathered early in Seattle's Cal Anderson Park and say they are planning to picket fast food restaurants around the area throughout the day, then gather again at 4 p.m. in Westlake Park.
The protesters picketed Wednesday night at a McDonald's restaurant on Seattle's First Hill - a preview of what could happen at other restaurants all over the city on Thursday.
Their first target Thursday was an International House of Pancakes outlet on Madison Street, where they chanted, "Walk out, we got your back," and "Show me $15."
The fast-food workers are taking credit for Seattle Mayor Ed Murray's proposal to raise the minimum wage to $15 an hour.
His plan would phase in the minimum wage over seven years. But many people striking in Seattle say they want an immediate $15-an-hour wage.
As the plan is being debated by the Seattle city council, businesses are sounding the alarm that raising the wage too quickly could hurt their revenue and force them to hire fewer workers or let go of some employees.
Popular restaurateurs have emphatically argued for counting tips in total compensation.
Minority chambers of commerce have banded together to argue that a quick hike to $15 would kill their family-run businesses. Their argument: Who is going to hire immigrants learning English for $15 an hour?
OneSeattle, a group made up of small and medium-size employers with the backing of large business organizations like the Washington Restaurant Association, says it supports a wage hike, but with some key caveats.
The group wants a phase-in and a temporary training wage. It also wants health care, commissions, tips and bonuses to be counted in total wages.
Mayor Ed Murray presented his plan, forged from an agreement among labor, business and nonprofit representatives. The group crafted a plan that 21 of the 24 members agreed on. It created a unified front for Murray to present to the city.
Murray's proposal gives businesses with more than 500 employees nationally at least three years to phase in the increase.
Those providing health insurance will have four years to complete the move. Smaller organizations will be given seven years, including a consideration for tips and health care costs over the first five years of the phase-in.
"If you leave the negotiating table with both sides being a little unhappy, you've got a pretty good deal because it's sustainable," David Freiboth of the King County Labor Council told City Council members, invoking an old labor saying.
Once the $15 wage is reached, future annual increases will be tied to the consumer price index.
The current minimum wage in Washington state is $9.32 an hour.