A tender boat, also known as a tender, is a smaller boat or ship used to service or support larger boats or ships. Tender boats are used to transport people or supplies to and from shore or another ship. Tender boats can be used for a variety of purposes, including fetching supplies and equipment, transporting passengers, or simply providing a casual ride on the water. They can also serve as lifeboats during an emergency. Tender boats are often carried by larger vessels and can be hoisted onto the deck for safe and secure storage or towed behind the yacht for quick and convenient access to the water. Tender boats can navigate shallow waters that larger boats are unable to traverse. Tender boats often match the luxury and quality of the yacht itself and are usually loaded with convenience and comfort features, and may even have sleeping cabins and space for numerous passengers.

There are different types of tender boats, including:

• Ships Tender: A boat or ship used to service or support other boats or ships.
• Dinghy: A small boat that runs back and forth to a bigger boat (or ship) .
• Destroyer Tender: A large ship used to support a flotilla of destroyers or other small warships.
• Dive Tender: A ship or boat used to support the actions of divers.
• Fish Tender: A vessel that commercially supplies, stores, refrigerates, or transports fish, fish products, or materials directly related to fishing or the preparation of fish to or from a fishing, fish processing, or fish tender vessel or a fish processing facility.
• Seaplane Tender: Either a ship carrying multiple seaplanes, also known as a seaplane carrier, and considered to be a predecessor to the aircraft carrier; or a small craft used to support the operations of flying boats.
• Submarine Tender: A large ship used to support a flotilla of submarines.
• Torpedo Boat Tender: A ship used during the late 19th and early 20th centuries to carry torpedo boats to sea and deploy them against enemy ships.
• Yacht Tender: A craft that services an anchored or moored yacht.

Tender boats are also used in the cruise industry to transport passengers between the cruise ship and the port when the ship itself is unable to dock. These tenders are usually carried by the cruise ship and often double as a lifeboat.