Hot Tubs & Spas glossary

Plug-and-play means a tub designed to run on a standard 120V outlet rather than a dedicated 220V circuit. It avoids the electrician cost - Fixr puts a 220V outlet at $120-$200 with electricians at $40-$100 per hour - but heats much more slowly and generally runs fewer jets at once. That outlet still needs to be a suitable circuit; check the manufacturer's requirements.

Shell is the molded body you sit in, usually acrylic over a structural backing. Skirt or cabinet is the exterior paneling - This Old House prices cabinet materials from $2,000-$9,000 for synthetic wood up to $5,000-$12,000 for brick or faux stone. Equipment bay is the compartment holding pumps, heater, and control pack; access to it determines how expensive service calls are.

Salt cell is the component in a saltwater tub that converts dissolved salt into chlorine. It is a consumable that eventually needs replacing, which is the running cost saltwater buyers most often miss. Fixr puts saltwater tubs at $2,000-$20,000.

Swim spa is a long tub with a current generator for swimming in place - a distinct product at $15,000-$40,000, per Fixr. Cover lifter is the hinged arm that makes removing a heavy cover possible alone; it is close to essential and often quoted separately.