Welcome to 145 Chestnut Street, a beautifully maintained custom-built ranch set on a serene, park-like acre in the desirable Mount Sinai School District. Freshly painted interiors, spacious rooms, extra-wide hallways, and abundant natural light stream through quality Pella windows. Enjoy an inviting eat-in kitchen with center island, propane stove, two pantries, and scenic backyard views. Relax by the cozy wood-burning fireplace or unwind in the tranquil three-season room. The generous primary suite offers a large walk-in closet and an updated bath with new quartz vanity. The fully finished basement includes a convenient half bath with plumbing in place for a future shower. Practical highlights: central air, whole-house propane generator (8-day backup), 200-amp electric service, oversized insulated two-car garage with workshop space, front and rear sprinklers, a circular driveway lined with elegant pavers, and recently replaced roof and gutters. Perfectly located near Cedar Beach, Port Jefferson Station LIRR, commuter routes, and Long Island’s charming North Fork, this home blends comfort, convenience, and room to grow in a highly sought-after community.