Thirteen Westport merchants have pledged at least 10 percent of their sales on Sunday, Dec. 14, to one of three nonprofits in the region as part of a charity event.

The charity event, called "shop203," also includes a fundraising holiday party Dec. 14 at Post 154 restaurant, organizers said.

Participating merchants have pledged 10 percent or more of their Dec. 14 receipts to either White Plains, N.Y.-based Autism Speaks, which funds autism research and awareness programs; Fairfield-based CT Block Party, which awards grants to young people to fund charitable work; or to the Resiliency Center of Newtown, which promotes long-term healing of people affected by the December 2012 mass shootings at Sandy Hook Elementary School.

Merchants on Dec. 14 will display signs stating which of the three nonprofits they are supporting, shop203 organizers said in a news release.

Participating Westport merchants include: Calypso, 1 Main St.; Down Under, 575 Riverside Ave.; Freshii, 1 Main St.; JL Rocks, 292 Post Road East; Joie, 48 Post Road East; Jonathan Adler, 166 Main St.; and LeRouge by Aarti, 190 Main St.

Also: Shoe-Inn, 38 Main St.; South Moon Under, 14 Post Road East; Vineyard Vines, 90 Main St.; Walin & Wolff, 30 Post Road East; Winged Monkey, 384 Post Road East; and Wish List, 606 Post Road East

Attitude Dance & Active Wear, 330 Westport Ave. in Norwalk, will donate from its Dec. 13 sales because it will be closed Dec. 14.

The party is planned from 4 to 7 p.m. at Post 154, 154 Post Road East, and will include door prizes, a drawing for trees decorated by area designers, drinks, appetizers and live music, organizers said.

Tickets are $50, and all proceeds will be split evenly between Autism Speaks and CT Block Party, according to the release. Tickets are available online at www.shop203.com.

Shop203 co-founders Michelle Hogue and Lisa Neumyer said they organized the event to encourage shopping locally and help charities.