Hot tub cost dataset

The running cost, and which half is measured

⚠️ Being exact about which half of this is measured and which is modelled, because the distinction is the whole point of this site. The price of electricity is official: 18.11 cents per kilowatt-hour, the US average residential price for May 2026, year to date in EIA, Electric Power Monthly, table 5.6.B — residential price by state, retrieved 2026-08-25. The consumption is ours: a declared base by size, multiplied by a climate factor and a cover factor. Chemicals and filters are a declared estimate of $14 to $32 a month on top. Put your own bill’s rate in and the answer improves honestly. On the reference spa that comes to $819 a year and $23,675 over ten — 35% of which is owning rather than buying.

Size, weight and what it stands on

The weight column is the one that decides the base, and it is why the deck row exists at all. ⚠️ Filled and occupied, the reference spa is 5,000 lb on roughly forty square feet — several times what an ordinary domestic deck is designed for. Decks rarely fail dramatically under this: they sag, the spa goes out of level, it stops draining and stops sitting properly on its cover, and the repair costs more than the reinforcement would have. A swim spa at 12,000 lb is beyond any deck or patio slab and is a poured pad decision before it is anything else.

Line items

92% of the reference total comes from estimated rather than official figures. The reference job is a six to eight seat spa on a new reinforced pad with a 45 foot run from the panel: 21.1 trade hours across cement masons, electricians and general maintenance workers. ⚠️ Note that no line here is measured in hours — the labour sits inside lines measured per square foot, per linear foot and per unit, so the hours figure is summed from inside them rather than read off a quantity.

The reasoning behind each figure

The spa itself — two or three seatsestimated, ±41%

• A rotomoulded or entry acrylic spa at the bottom of the band and a well-insulated acrylic one from an established maker at the top.
• ⚠️ The insulation is where the price difference goes, and it is invisible on a showroom floor. Full-foam insulation costs more to buy and less to run for as long as you own it; a cabinet with a heater and nothing else is cheap for exactly one reason.
• This is also the size where a plug-in model exists, and it is the size where a plug-in model disappoints: on a normal circuit it heats or runs the jets, not both.

The spa itself — four or five seatsestimated, ±42%

• The size most gardens end up with: two adults can use it without negotiating and it still fits through a normal side gate on its trolley.
• The band is an entry acrylic tub at the bottom and a fully insulated one with two pumps at the top. As with every size on this page, the insulation is what separates the ends of the band and it is the part you cannot see in a showroom.

The spa itself — six to eight seatsestimated, ±44%

• A large acrylic spa with multiple pumps. The band is a mid-market tub at the bottom and a fully specified one at the top.
• Number of seats is a poor guide to how many people fit comfortably: a tub sold as eight-seat is a good six-seat. Sit in it before buying, which sounds obvious and almost nobody does.

The swim spa itselfestimated, ±38%

• A swim spa is a different product: several times the water, a propulsion system, and often two temperature zones.
• ⚠️ It also needs a base built for it. Twelve thousand pounds filled is beyond what a patio slab or any domestic deck will take, so a swim spa is a concrete pad decision before it is anything else.

New reinforced concrete pad — materialsestimated, ±34%

• Four inches of reinforced concrete on a compacted base, poured a foot larger than the spa all round so there is somewhere to stand and somewhere for the cover to go.
• Modelled at 80 square feet for a spa and 220 for a swim spa. It is a small pour, so the fixed costs of getting a crew and a mixer there are most of it.

New reinforced concrete pad — labour

• Modelled at 0.0775 hours per sq ft, the midpoint of a 0.055 to 0.1 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Excavated and compacted gravel bed — materialsestimated, ±52%

• Topsoil off, crushed stone in, compacted in layers and screeded flat. Perfectly adequate under a small spa and considerably cheaper than concrete.
• ⚠️ Compacted in layers is the whole thing. Gravel tipped into a hole and raked is not a base, and a spa on it settles unevenly within a year — which shows up first as a cover that stops sitting down properly.

Excavated and compacted gravel bed — labour

• Modelled at 6.5 hours per each, the midpoint of a 4.0 to 9.0 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Reinforcing the deck to carry the spa — materialsestimated, ±52%

• Extra footings under the spa position, doubled or sistered joists, and usually a beam — done from underneath an existing deck, which is the reason for the hours.
• ⚠️ This line exists because the alternative is a deck that fails. A filled six-seat spa concentrates around two and a half tons on roughly forty square feet, which is several times what a domestic deck is designed for. Decks do not usually collapse suddenly under this; they sag, the spa goes out of level, and the repair is worse than the reinforcement would have been.
• The band is how much of the deck has to come up to get at the framing and whether the footings can be dug from below.

Reinforcing the deck to carry the spa — labour

• Modelled at 21.0 hours per each, the midpoint of a 12.0 to 30.0 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

240 volt circuit, GFCI disconnect and the run to the spa — materialsestimated, ±37%

• A dedicated 240 volt circuit with ground-fault protection and a disconnect within sight of the spa but set back from it, so that somebody can cut the power without reaching over the water.
• ⚠️ Priced per foot of run because that is what it scales with, and the run is the number people underestimate: the panel is usually at the front of the house and the spa at the back. Add a fixed allowance for the disconnect and the terminations, which is in the band.
• This line assumes the panel has room and capacity for the circuit. If it does not, that is a service upgrade — our electrical panel upgrade calculator prices it, and it is a four-figure surprise.

240 volt circuit, GFCI disconnect and the run to the spa — labour

• Modelled at 0.13 hours per linear ft, the midpoint of a 0.09 to 0.17 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Delivery and setting it in place — materialsestimated, ±54%

• Delivered on its side on a trolley and walked into position, which needs a clear route of about four feet and a gate that comes off its hinges if necessary.
• Measure the route before buying the tub. It is the most avoidable problem on this page and one of the most common.

Delivery and setting it in place — labour

• Modelled at 3.5 hours per each, the midpoint of a 2.0 to 5.0 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Craning it over the house or the fenceestimated, ±58%

• A half-day crane hire and the banksman, for the gardens with no route in.
• ⚠️ Worth pricing before choosing the spa rather than after. A smaller tub that fits down the side passage can be cheaper all in than a bigger one that has to fly, and the crane bill does not appear in any showroom conversation.

Steps and a surround — materialsestimated, ±63%

• Steps up to the rim and a surround that closes the gap between the cabinet and whatever it stands on.
• It is a comfort item on a small spa and much closer to a necessity on a 54 inch one, which is a long way up in bare feet.

Steps and a surround — labour

• Modelled at 4.0 hours per each, the midpoint of a 2.0 to 6.0 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Cover lifter — materialsestimated, ±51%

• Looks like an accessory and behaves like a running cost. A cover that is awkward to lift gets dragged on the ground, gets damaged and stops sealing — and a cover that stops sealing is the biggest single item on the electricity side of this page.

Cover lifter — labour

• Modelled at 1.0 hours per each, the midpoint of a 0.5 to 1.5 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Filling it, first chemistry and commissioning — materialsestimated, ±54%

• Fill, balance, sanitise and check it through a full heat-up, which on a large tub from cold takes the best part of a day.
• The starter chemicals are in here. What is not in here is the weekly routine afterwards, which is the part that keeps the water safe rather than merely clear.

Filling it, first chemistry and commissioning — labour

• Modelled at 2.25 hours per each, the midpoint of a 1.5 to 3.0 band. Labour is a separate line from material because the regional multiplier applies to hours and never to what things cost to buy.

Not included in this dataset

A service upgrade if the panel is full

The circuit assumes there is room in the existing panel. A spa is a substantial 240 volt load and an older panel often has neither the space nor the capacity, which turns into a separate job priced on our electrical panel page.

Permits, setbacks and what your area requires

⚠️ Many jurisdictions treat a spa like a pool: barrier rules, setbacks from boundaries, an electrical permit and an inspection. Some are satisfied by a lockable hard cover. One call to the building department settles it and there is no national answer to publish here.

Replacing the cover

A cover has a life of roughly three to seven years and it is the part whose decline you do not notice. Its replacement is not in the purchase price and it belongs in the ownership figure — which is why this page runs the numbers with a worn cover as well as a good one.

Repairs, and what happens at the end

Pumps, heaters and control packs fail, and an out-of-warranty control pack is a serious bill. At the far end, disposing of an acrylic spa is its own small project.

Water beyond the first fill

A spa gets drained and refilled a few times a year. On a metered supply that is a real if small number, and on a private well it is a question about recovery rate rather than about money.