The Dallas Morning News said Sunday that Jonas, 17, made the pledge after touring the North Texas Food Bank in Dallas Saturday to the delight of 140 volunteers on hand.
After touring the facility, Jonas contacted his father, Kevin, before announcing the financial pledge to the non-profit site.
Saturday's visit was part of a joint venture involving the national food bank network, Feeding America, and the TV series "The Biggest Loser."
Food bank president Jan Pruitt applauded the pledge by Jonas, the youngest of the three Jonas Brothers members.
"This is our next generation of philanthropists," she said of the young pop singer. "His time here with these couple of hundred kids that are out here volunteering today -- they're going to find out, 'Well, (if) it's important to him, it should be important to me.'"