Lunch at New York City public schools will be available free of charge to all 1.1 million students beginning this school year, Carmen Fariña, the schools chancellor, said on Wednesday in the basement cafeteria of a Hell’s Kitchen elementary school. The new school year begins on Thursday.

“This is about equity,” Ms. Fariña said. “All communities matter.”

This move has been long sought by food-policy advocates and many members of the New York City Council, who said that some students would prefer to go hungry rather than admit they cannot afford to pay for lunch. Nationally, the practice of “lunch shaming” — holding children publicly accountable for unpaid school lunch bills — has garnered attention.

The vast majority of New York City public school students are poor: About 75 percent of them had already qualified for free or reduced-price lunches, officials said, and in New York City those who qualified for the lower cost received it for free, as well. Still, the new initiative will reach an additional 200,000 students and save their families about $300 per year. The full price for a school lunch is $1.75 per day.

By offering free lunch to all students, New York joins other major cities including Boston, Chicago, Detroit and Dallas, according to Liz Accles, the executive director of Community Food Advocates, which had organized a campaign in support of the policy. But New York has far more schoolchildren to feed than any of those cities.

City officials said the program was not expected to cost the city more money. The state recently changed how it tracks families that are eligible for benefits like Medicaid, matching them with the schools their children attend. With that new system, the city was able to identify more students whose families receive those benefits, enough that the whole city qualifies for a federal program that pays for universal free lunch.

Elizabeth Rose, the education department’s deputy chancellor of operations, urged families to continue to fill out household income forms, which are used to determine if schools receive Title I money, a federal program that funnels extra funding into schools with lots of poor students.