A mill dam (International English) or milldam (US) is a dam constructed on a waterway to create a mill pond.^[1]

Water passing through a dam's spillway is used to turn a water wheel and provide energy to the many varieties of watermill. By raising the water level so that the overflow has farther to fall, a milldam increases the potential energy that a mill can harness and use for various tasks.^{[citation needed]}

Listed are here are some of the many examples of historic milldams and millponds (or place names taken from them).

• Bramley Millpond in Bramley, Surrey
• Ifield Millpond in Ifield, West Sussex
• Valebridge Millpond on the outskirts of Burgess Hill, West Sussex
• Mill Dam, Shapinsay in the Orkney Islands

• Milldam Rice Mill and Rice Barn in Georgetown County, South Carolina
• Atwater Millpond in Kalamazoo County, Michigan
• Ballardvale Millpond in Ballardvale, Massachusetts
• Bigler's Millpond in Bigler's Mill, Virginia
• Crump's Millpond in Quinton, Virginia
• Gardy's Millpond in Westmoreland and Northumberland County, Virginia
• Glovers Millpond in Glascock County, Georgia
• Goodrich Millpond in Genesee County, Michigan
• Goodwin's Millpond in Marlboro County, South Carolina
• Hands Millpond in Cape May County, New Jersey
• Merchants Millpond State Park in Gates County, North Carolina
• Millpond, a small lake in Butler, New York
• Millpond Acres in Sussex County, Delaware
• Millpond Park in Mount Pleasant, Michigan
• Millpond Plantation in Thomas County, Georgia
• Millpond Reservoir in Burlington, Massachusetts