Going from four seats to six sounds like a small step. In practice, a 6-person spa holds more water, weighs more, and takes longer to heat, and those changes shape where it can go and how you power it.
This article covers what changes at six seats. For the rest of the hot tub decisions, start with the hot tub buying guide.
Short answer: plan for roughly 2,000–3,000 lbs of water, a proper pad, and 240V power if you want reasonable heat-up times.
Two 6-person examples
| AquaRest Premium 600 | Jacuzzi J-335 | |
|---|---|---|
| Seats | 6 (bucket seating) | 5–6 |
| Water | 240 gal | 360 gal |
| Size | 78 × 78 × 32 in. | 84 × 84 × 36 in. |
| Jets | 29 stainless | 42 PowerPro |
| Dry weight | 295 lbs | Not stated in our data |
| Power | 110V/15A or 230V/30–40A | Not stated in our data |
| Price | $3,479 (AquaRest) | Dealer quote |
From AquaRest and Jacuzzi listings, checked September 2026.
What changes
Water and weight. At 8.34 lbs per gallon (USGS), the Premium 600’s water weighs about 2,000 lbs and the J-335’s about 3,000 lbs. Add the shell and six adults.
Heat-up. By EIA’s Btu definitions, warming 240 gallons from 60°F to 102°F takes about 24.6kWh. That’s about 25 hours on the Premium 600’s 1kW (110V) heater, or about 6 hours on its 4kW (230V) heater, before heat loss.
Jets per seat. The Premium 600 has 29 jets for six seats; the J-335 has 42. More jets doesn’t always mean better massage, but it does mean more pump load.
Delivery. An 84-inch-square spa needs a clear path at least that wide on its side, or a crane.
Here’s what the spec sheet won’t tell you: a 6-person spa is mostly used by two or three people. If that’s you, a 4-person spa heats faster and costs less to run.
Before you buy
- Confirm the pad or deck can carry the filled weight plus people.
- Plan on 240V unless you’re fine with day-long heat-ups.
- Measure the delivery path.
- Count how many people will use it most weeks.
My rule of thumb: size for your usual group, not your biggest party.
Run the numbers on the load
The AquaRest Premium 600 weighs 295 lbs dry and holds about 2,002 lbs of water, so about 2,297 lbs before anyone gets in. Its 78 x 78 inch shell covers about 42 sq ft. That is roughly 54 lbs per sq ft.
Now fill the seats. As an illustration, six adults at 175 lbs each add 1,050 lbs. The total reaches about 3,350 lbs, or about 79 lbs per sq ft.
The Jacuzzi J-335’s water alone is about 3,002 lbs on 49 sq ft, around 61 lbs per sq ft before the shell or the bathers. Our data has no dry weight for it.
Don’t assume a deck can carry loads like these. Plan on a concrete pad, or an engineer’s review of the deck.
Price per seat
More seats can cost less per seat, within one brand:
| Spa | Seats | Price | Per seat |
|---|---|---|---|
| AquaRest Premium 300 | 2 | $3,199 | about $1,600 |
| AquaRest Standard 400 | 4 | $2,799 | about $700 |
| AquaRest Premium 600 | 6 | $3,479 | about $580 |
Our arithmetic from AquaRest’s listed prices.
The six-seat spa is only $280 more than the two-seat one. The purchase price is the small part of sizing up. The water, the weight, and the heating are where it costs you.
What a refill costs to heat
Warming 240 gallons from 60°F to 102°F takes about 24.6 kWh, around $4.50 at the 2026 US average of 18.34 cents per kWh. The J-335’s 360 gallons take about 37 kWh, around $6.80. Those are small sums. The time is the problem: on a 1kW heater, 24.6 kWh is a full day.
Jets per seat
The Premium 600 has 29 jets for 6 seats, under 5 per seat. The J-335 has 42 for 5 to 6 seats, at least 7 per seat. If massage is your reason for buying, look at how the jets are shared out by seat, since some seats in any spa get far more than others.
To compare smaller spas with published prices, see our hot tub comparison.
Bottom line: six seats means more of everything: water, weight, heat-up time, and running cost.
Sources
- AquaRest Discover Premium 600 and Jacuzzi J-335 listings (capacity, dimensions, jets, power, weight, price), checked September 2026
- U.S. Energy Information Administration, “British thermal units (Btu),” accessed October 5, 2026: eia.gov
- U.S. Geological Survey, “Water Density,” accessed October 2, 2026: usgs.gov
- U.S. Energy Information Administration, Electric Power Monthly, Table 5.6.A (residential average 18.34¢/kWh, June 2026 data), accessed October 1, 2026
- AquaRest Discover Premium 300 and Standard 400 listings (price, seats), checked September 2026