Putting a swim spa in the ground

Yes, if the maker allows it. Sinking a swim spa fully puts its rim at ground or deck level; sinking it part way lowers the step-in from a median 53 in. Of the 186 swim spas we track, 105 are approved for it in the maker's manual or spec sheet and 28 are not: every Arctic Spas model, the Endless Pools X500 and Endless Pools X2000 and every PDC Spas model. For the other 53 the maker doesn't say, so ask before you plan a hole.

A hole is not enough. The makers' manuals set conditions that shape the whole dig:

• A pit with room to work. Master Spas asks for at least 3 ft of service space around the whole cabinet. Hydropool describes a separate concrete-walled container with 2 to 3 ft of access on every side; without one, it says, any repair means lifting the spa out.
• Drainage. The equipment bay must never stand in water. Master Spas wants a drainage system designed to the local authority's rules for rain, runoff and draining the spa, and says the unit is not built to be submerged.
• Air. Master Spas asks for ventilation to clear moisture and keep the equipment from overheating.
• No backfill. The spa has to sit on a base built for its full weight, not on packed soil. Master Spas voids its warranty if the cabinet is backfilled with sand, gravel or earth.
• A contractor's design. Endless Pools allows in-floor installs only with access for service and proper drainage, and tells owners to have a certified contractor sign off on the final design.

Pumps, heaters and control boxes wear out, and they sit behind the cabinet panels. Once the spa is in the ground, a deck, a wall or soil can be in the way. Master Spas' warranty is blunt about who pays: if the spa has to come out for a repair, removal, damage to landscaping, decking or fencing, and the cost of getting to the spa are the owner's, and access charges apply if the spa isn't reasonably accessible.

In our check of service access, 8 of the brands we track pass and 9 pass only partly. Swim spa service access explains what to look for, brand by brand.

• American Whirlpool (passes our check): No foam to dig through and ordinary pumps, but the spa must stay reachable on all four sides.
• Arctic Spas (passes our check): Removable doors on all four sides and a foam-free cabinet; Arctic asks for 24 in of clearance all round and recommends above-ground installs.
• Artesian Spas (partly passes): Ordinary pumps and jets, but full foam, dealer-only parts and no stated clearance.
• Bullfrog Spas (passes our check): Keep all four sides open: the pumps, heater and a mainstream Gecko control pack sit behind removable panels.
• Cal Spas (passes our check): Ordinary pumps behind screw-on panels and no foam in the way; keep 3 feet clear on every side.
• Coast Spas (partly passes): Keep every side reachable: Coast's manual says the equipment must stay accessible and the spa liftable out of any enclosure, but gives no clearance figure.
• Dynasty Spas (passes our check): Removable panels on all four sides, published service clearances, and panel insulation around an open air space rather than foam fill.
• Endless Pools (partly passes): Panels lift off and Endless asks for 2 feet of clearance, but the E-Series propeller needs scheduled hydraulic overhauls.
• Hydropool (passes our check): Built to be serviced: removable panels, blanket insulation away from the shell, Gecko controls, and published clearance rules of 2 ft all round.
• Jacuzzi (passes our check): Jacuzzi requires access to every side (24 in crawl space, 3 ft at the equipment end when recessed), and the current runs on ordinary jet pumps.
• LPI (passes our check): Ordinary jet pumps and Balboa controls behind a marked equipment end; LPI asks for 24 in of clearance there but won't pay to open up decking.
• Marquis (partly passes): Keep every side reachable: the V150 warranty makes access your job, and full foam makes a leak a dig-out. Marquis publishes no clearance figure.
• Master Spas (partly passes): Every skirt panel comes off and Master Spas asks for 3 feet all round; if the spa is boxed in, access costs are the owner's.
• PDC Spas (partly passes): No foam to dig through and 3 ft of clearance asked, but PDC's own schedule replaces TruSwim's hydraulic motors, lines and props at 3 years.
• Sundance Spas (partly passes): Gecko packs, but no published service clearance; on the Surf, an actuator that won't calibrate is a retailer repair.
• SwimEx (partly passes): SwimEx designs for access: in-ground pools need a 3 x 3 ft hatch (or panels above ground) and a ladder down to the pump, filter and heater in the pit, and the drive sits at the back under the decking. That is a recessed install with a way in, which our checklist rates acceptable rather than best.
• Wellis (partly passes): Needs 60 cm (2 ft) clear all round; standard Gecko controls, but Wellis-only jets from Hungary.

More than one on a pad. Hydropool, a swim spa maker, puts the extra in-ground work at about $10,000 to $20,000, and says landscaping around a swim spa often runs $3,000 to $10,000, more for in-ground sets. It doesn't say whether those are US or Canadian dollars.

The line items to price with your contractor: excavation, the pit's walls and floor, drainage, ventilation, a service hatch or removable decking, the electrical run and, where the truck can't reach, a crane. The spa's own price and the rest of the bill are on what a swim spa costs.

The same ones as above ground, with water closer to the wiring. Under NEC Article 680 the disconnect stays at least 5 ft from the spa's inside wall and within sight of it, and metal within 5 ft of the inside wall is bonded with #8 copper, as one Colorado building department summarizes the 2023 code. Master Spas adds that standing water must never reach the electrical equipment.

A licensed electrician sizes and places it all, under a permit where your town requires one. Amps and circuits for every model are on swim spa electrical requirements. If you're weighing a dug-in swim spa against a pool or a hot tub, see swim spa vs pool and swim spa vs hot tub.