Swim spa cost calculator

What the legal standby ceiling costs a year

California’s appliance efficiency rules give swim spas their own row. Table G-5 of Title 20 sets a maximum normalized standby power for portable electric spas built on or after June 1, 2019, and it names “exercise spas and the exercise spa portion of combination spas” apart from standard spas. The ceiling is a formula of the fill volume alone: 3.75 times the volume in gallons raised to the power two-thirds, plus 40 watts. The larger the tank, the higher the ceiling, but more slowly than the volume, because heat leaves through the surface and the surface grows slower than the volume.

The calculator applies that formula to the volume you enter. For the Royal Swim Spa, a 15 ft model the seller lists at about 1,960 gallons, the ceiling is 627.31 W. Held for the 8,760 hours of a year, that is 5,495.3 kWh. At the U.S. residential price EIA published for August 2026, 18.16 cents per kWh, the ceiling costs $997.94 a year, or $83.16 a month. Those figures are the defaults of the tool above, and they match the hand check written in the audit for this page.

Read the result for what it is. The ceiling is the most a compliant exercise spa may draw in a standardized standby test, not a meter reading. The test is normalized to a 22 °F difference between the water and the air; for a unit that keeps at least 100 °F through the test the table normalizes to 37 °F instead, with the same formula. A warm night uses less than the test, a freezing one can use more, and hours of swimming against the current add pump power that the standby figure does not count. What the ceiling gives you is a defensible upper bound for the idle part of the bill, computed from a number on the spec sheet, which no seller page read for this page prints.

The four rows above come from the spec sheets read. Sundance prints a volume for each swim spa it lists: 964 gallons for the 13 Stream, 1,233 for the 12 Splash and 1,929 for the 17 Surf. Royal Spa prints about 1,960 gallons for its 15 ft model. The model names do not predict the tank. The 12 Splash and the 13 Stream share the same outside dimensions, 149 × 92 in, yet the Splash holds 1,233 gallons and the Stream 964; the Splash’s ceiling is 471.19 W and the Stream’s 405.95 W. Ask for the fill volume of the exact model, not its length, before you compare running costs.

The 17 Surf and the Royal Swim Spa hold almost the same volume, 1,929 and 1,960 gallons, so their ceilings sit within a few watts of each other, 621.10 and 627.31 W, although one is listed at $53,599 and the other at $28,595. The standby ceiling says nothing about the quality of the insulation, only about the limit a unit has to meet to be sold in California. A unit that tests well below its ceiling costs less to keep warm, and the product pages read do not publish that measured figure.

The electricity price behind the dollars

The dollar figure is the ceiling multiplied by a price, and the price moves more than the ceiling. EIA’s Electric Power Monthly, released October 23, 2026, gives the residential price of August 2026 for every state. The calculator offers each of them, and a field for the price on your own bill, which is the better number when you have it.

The same 1,960-gallon ceiling of 5,495.3 kWh a year costs $997.94 at the U.S. figure of 18.16 cents, $1,634.84 at California’s 29.75 cents, and $2,592.66 at Hawaii’s 47.18 cents. The table below lists every state as EIA printed it, with the August 2025 figure beside it; EIA marks the 2026 values as preliminary. Multiply the 5,495.3 kWh by your state’s cents and divide by 100 to check any row by hand.

Cover or barrier: what ISPSC 305 asks around a swim spa

The International Swimming Pool and Spa Code does not treat a swim spa as a pool. Its definitions call an exercise spa, “also known as a swim spa”, a variant of a spa. That word decides which sentence of section 305 applies. The section asks for a barrier around outdoor pools and spas, then exempts the area of a spa or hot tub equipped with a lockable safety cover complying with ASTM F1346 from sections 305.2 through 305.7. A pool needs a powered safety cover to earn the same exemption; a spa needs a lockable one.

The calculator reads your answer to the cover question in exactly those terms. With a lockable cover that complies with ASTM F1346, it returns that the model code does not ask for a barrier, and it does not price one. With any other cover, or if you are not sure, it returns that a barrier is expected under 305.2 and checks the height you plan against item 1 of 305.2.1: the top of the barrier at least 48 in above grade, measured on the side away from the spa, around the whole perimeter and for 3 ft horizontally outside it. A 54 in barrier passes; a 42 in one does not, and the tool says so.

A swim spa stands tall. The models read here range from 49 to 53 in high, and the Royal Swim Spa is 50 in. Item 4 of the same list covers a spa whose top is above grade: the barrier goes on grade or is mounted on top of the spa structure, with no more than 4 in between the top of the spa and the bottom of the barrier. The calculator does not decide whether the cabinet wall itself can serve; that depends on the rest of section 305 and on the building official.

Two cautions. The text here is the 2021 model code as adopted in New Hampshire, read on UpCodes; a state or city can amend it, and some adopt an older edition or their own pool barrier ordinance. And the exemption rests on the cover, not on the spa: a cover sold with the unit is not automatically a lockable cover complying with ASTM F1346. Ask the seller for the cover’s standard in writing, enter the barrier figures if you plan one anyway, and confirm the local adoption before you budget either. If that barrier is frameless glass, the glass pool fence calculator checks the gap under each panel and the gate latch.

What three sellers print for a swim spa at your length

Three sellers print prices that can be read model by model. Sundance Spas, a manufacturer, prints an MSRP on each swim spa product page and adds that final pricing varies by dealership. Royal Spa, a manufacturer that ships nationwide, prints one price on its swim spa page and states that installation is not included. Aqua Living, a dealer, prints listing cards, each with an original price struck through and a current sale price. The calculator stores all sixteen prices as printed on October 24, 2026, and uses the current price for the Aqua Living cards.

Swim spas are sold by nominal length, so the calculator compares by length. A model fits your length when its name gives that length, when it is one of the two lengths of an “18′ & 20′” title, or when your length falls inside a “14′ to 16′” range, ends included. At 15 ft three listings fit: $18,699, $21,199 and $28,595, so the median is $21,199. At 16 ft five Aqua Living cards fit, from $18,699 to $27,499. At 20 ft the two 18′ & 20′ cards fit, both at $29,999. A length that no title names, such as 24 ft, returns no listing rather than a price borrowed from the next size.

Across all sixteen, the lowest price is $18,699 and the highest $53,599, with a median of $27,399. The spread is wide because the listings are not the same product: a 12.6′ Regatta and a 21′ dual-temperature model share a page, and an MSRP sits next to a sale price. The median marks where the middle listing of these three catalogs sat on one day. It is not a market price, and the page never mixes these listings with the published bands below.

Published price bands, kept apart from the listings

Three of the guides that lead the search results print bands instead of models. Endless Pools gives $25,000–$40,000 for a compact 12–14 ft swim spa, $20,000–$45,000 for a mid-size 15–17 ft one and $30,000–$80,000 or more for 18–20 ft and longer, then prices the installation lines one by one: standard delivery from $500, crane delivery from $1,000, electrical installation and panel upgrades from $1,000, and $5,000–$20,000 or more for installation as a whole. Jacuzzi, in a guide titled for 2025, puts entry-level models at $15,000–$17,000, mid-range at $18,000–$20,000 and high-end from $30,000, with delivery at $800–$1,500. Sundance, writing about Costco, puts Costco swim spas in 2026 at $10,000–$25,000 before installation, with 50-amp electrical service at $500–$1,500.

The bands disagree in ways worth noticing. Endless Pools’ mid-size band starts below its compact band. Jacuzzi’s mid-range tops out at $20,000, while the sixteen listings read start at $18,699 and only three of them sit under $20,000. A band is a seller’s summary across its own options and sites, which is why the table keeps each one with its publisher and the calculator never folds a band into the median of the listings.

Read a swim spa quote line by line

The spa is one line of the job. Enter the quote the way it is written, one line per field.

• Swim spa. The unit at the model and options quoted. The tool places this line among the listings at the same length: below the lowest, between, or above the highest.
• Delivery and crane. Endless Pools prices crane delivery as its own line; a narrow side yard can make it necessary.
• Electrical work. The spec sheets read call for a 240 V supply on a GFCI-protected circuit: 40 A for the 12 Splash and the 13 Stream, 48 A for the 17 Surf, and a 50 A dedicated circuit for the Royal Swim Spa.
• Pad. Priced on its own quote. No pad quantity is computed here.
• Cover. If the quote names a lockable cover complying with ASTM F1346, note it: it is the line that can remove the barrier.
• Barrier. Computed from the run and the price per foot you enter, never from a stored price.
• Permit fee and other lines: water to fill the tank, sales tax, landscaping, or anything else written on the quote.

A blank field means the line is not part of this job; a zero means it is included in another line. The total is the sum of what you entered and nothing else. For example, the 12 Splash at its MSRP of $27,299, with $1,500 of electrical work and a 60 ft barrier run at $40 a foot, which comes to $2,400, totals $31,199. At 12 ft the Splash is the only listing, so its MSRP sits within the range. A spa line of $18,000 against all sixteen listings sits below the lowest, which is the question to ask the seller: what does this price leave out? These amounts are test figures, not market prices.

The calculator never fills a price field from the listings. A listing shows what one seller printed for one model; your quote shows what your swim spa costs at your address. If the tile band of a pool is also on your list, the waterline tile count for a rectangular pool works it out wall by wall.

Swim spa cost questions

Read the result with its boundaries

• The standby figure is the Title 20 ceiling for exercise spas, a California rule, computed from the fill volume you enter. It is not a measured value of any model and not a bill.
• The barrier checks read the 2021 ISPSC model text as adopted in New Hampshire. Local amendments, older editions, pool barrier ordinances and homeowner association rules are not read; the local building department decides.
• Prices are what three sellers printed on the day read, for their own models and locations. They are never averaged with each other or with a published band.
• No pad, slab or ground figure is computed. The pad is a quote line.