A standard walk-in closet has dimensions of 7 feet by 10 feet at a minimum and an average of 100 square feet. Remember that the dimensions of the closet aren’t necessarily the usable space. This means that a 100-square-foot walk-in closet with shelves on each wall and an island may only have a walkable area of 50 square feet or less. Make sure you consider the effect of additions when you plan the room—mockups are a great idea.

On average, building a custom or built-in closet costs around $2,100. However, the total price can range from as little as $500 for a simple DIY project to $6,000 or more for a large, high-end custom closet. Most projects typically fall between $1,500 and $5,000.

The final cost depends on several factors, including the closet's size, type, materials, and features. Here is a general cost breakdown by closet type:

• Reach-in closet: $500 to $1,500

• Walk-in closet: $750 to $5,000

• Wardrobe: $2,000 to $6,000 or more

Choosing a prefabricated closet system is generally less expensive than a fully custom build. The scope of design and construction services will also significantly impact the price.

Some features and upgrades you can add (some of which increase the closet’s value) are: modular shelving, motion-activated lighting, climate control, custom lighting, cigar humidors, revolving shoe racks, jewelry shelves, custom woodwork, and built-in laundry hampers. While only truly luxury closets have all of these, many custom closets have at least one special feature listed above. 

Yes, adding a built-in or custom closet generally increases your home's value and makes it more attractive to potential buyers. A well-designed closet adds utility, organization, and a touch of luxury, which are appealing selling points. Most homeowners see a return on investment (ROI) of 50% to 60%; for example, a custom closet can add about $1,000 to your home's value on average. The specific ROI depends on the type, with custom walk-in closets typically providing more value than reach-in closets. However, to maximize value, ensure the closet doesn't significantly detract from the room's usable square footage. Converting an entire room into a closet can actually lower your home's value. Similarly, using overly lavish materials may not recoup their cost. A good strategy is to add a closet that takes square footage from a non-living area, such as a garage, to create a mudroom closet.