Welcome to 3876 Billberry Dr, an exceptional “William Shakespeare” model in the highly desired Kensington Square community. Beautifully maintained and thoughtfully upgraded by the original owner, this spacious home offers an ideal blend of elegant design, everyday comfort, and flexible living spaces. A charming English garden-inspired entry with low-maintenance roses and landscaping sets the tone before you step inside to sun-filled interiors, cinnamon maple hardwood floors, and expansive windows throughout. The main level features a rare alternate layout with a private office just off the kitchen, plus a bright kitchen, morning room, and family room framed by dramatic two-story windows with remote-controlled Hunter Douglas window treatments. A two-sided fireplace, home theater system, whole-home sound/intercom system, oversized deck, and large brick patio create excellent indoor and outdoor entertaining options. The mudroom is roughed in for a full bath and stackable washer/dryer, adding future flexibility. The fully finished lower level expands the home with approximately 1,000 square feet of luxury vinyl plank flooring, a spacious recreation room, second fireplace, second home theater/sound system, kitchenette/bar with refrigerator and dishwasher, ensuite fourth bedroom, generous storage, and flexible space for guests, fitness, work, or extended stays. Upstairs, the impressive primary suite offers a bay window, two closets, a large bath with jacuzzi tub, and a loft area with a separate laundry space. Two additional generously sized ensuite bedrooms include walk-in closets and sound system connectivity. Enjoy exceptional access to Fairfax County Parkway, Route 50, Dulles International Airport, Chantilly, Herndon, Reston, Tysons, Fair Oaks Hospital, Fair Lakes, Fair Oaks Mall, Greenbriar Shopping Center, and nearby dining, retail, recreation, and commuter routes. Zoned for Navy Elementary, Franklin Middle, and Chantilly High School.