The Senate voted 30-23 Wednesday evening, a day after the House backed it.
The state's minimum wage is $8.25. The proposal would raise it incrementally until 2022. The plan also includes a tax credit for some small businesses.
Democratic Sen. Kimberly Lightford is a sponsor. She says it's the best chance to raise wages and improve living conditions for many Illinois residents.
But opponents worry about the impact on businesses. Republican Sen. Kyle McCarter of Lebanon calls raising the wage an "artificial way" of helping people.
Gov. Bruce Rauner's spokeswoman didn't immediately return a message Wednesday. The Republican has said he'd support a minimum wage increase in conjunction with other regulatory changes.