Key facts
| Item | June to September | October to May |
|---|---|---|
| Standard, first 400 kWh | 9.8332 cents | 8.7020 cents |
| Standard, above 400 kWh | 12.5263 cents | 11.0852 cents |
| Time of use, on peak (6 to 10 p.m. Mon to Fri) | 33.6173 cents | 29.7498 cents |
| Time of use, off peak (all other hours) | 7.4705 cents | 6.6111 cents |
| Customer charge, single family, single phase | $12.00 a month | |
| Riders on energy (price summary, Sept 25, 2026) | Schedule 94 7.63%, Schedule 193 3.84%, Schedule 92 1.78%, Schedule 198 0.17%, Schedule 98 minus 0.53%: about 12.9% | |
| Time of use minimum term | One year | |
Sources: Rocky Mountain Power Utah Electric Service Schedule No. 1; Rocky Mountain Power State of Utah Price Summary, in effect September 25, 2026; Salt Lake City Building Services FAQ.
The break even, worked out
For the extra kWh a hot tub or sauna adds, the standard rate charges the upper block price, since most Utah homes pass 400 kWh a month anyway. In winter that is 11.0852 cents. Time of use charges 6.6111 cents off peak and 29.7498 cents on peak. Solve for the on peak share where the two match: 6.6111 plus 23.1387 times the share equals 11.0852, so the share is about 19.3 percent. The summer math lands at the same place: 7.4705 plus 26.1468 times the share equals 12.5263, again about 19.3 percent. If less than roughly a fifth of the added energy is used between 6 and 10 p.m. on weekdays, time of use is cheaper for that load. Remember the plan applies to the whole house, so run the same test on your past bills before enrolling.
Hot tubs: heat before 6, coast through the peak
A hot tub's heater runs to recover heat lost through the cover and after each soak. Most controllers allow filter and heat cycles to be scheduled, so on time of use set them to finish before 6 p.m. and resume after 10 p.m. on weekdays. How much the water cools over the four peak hours depends on the cover, insulation and weather, so check your own tub's drop on a cold weeknight before relying on the schedule. A 4 kW heater, the size in the MyHotTub Victoria, costs about 26 cents an hour off peak in winter, 44 cents at the standard upper block and $1.19 on peak, before riders. A 120 volt plug and play tub with a 1 kW heater, such as the MyHotTub Sierra, costs a quarter of each of those, but recovers so slowly that it may need to heat into the evening, which makes the schedule harder to keep.
Saunas: the session time decides it
A sauna heater draws its full rating while the room heats and then cycles. A 6 kW heater at full draw uses 6 kWh an hour: in winter about 40 cents off peak, about 67 cents at the standard upper block and about $1.78 on peak. An evening sauna three weeknights a week on time of use, with an hour of heating and use each time, puts most of that load on peak and costs more than the standard rate. Move the same sessions to before 6 p.m., after 10 p.m. or to weekends and time of use becomes the cheaper plan by a wide margin. An 8 kW heater raises every figure by a third.
Riders that sit on top
The tariff prices are base rates. The price summary in effect September 25, 2026 adds percentage adjustments to energy charges: 7.63 percent under Schedule 94, the energy balancing account, 3.84 percent under Schedule 193 for demand side management, 1.78 percent under Schedule 92, 0.17 percent under Schedule 198, and a credit of 0.53 percent under Schedule 98. Combined, they add roughly 13 percent to every figure in this guide. They apply to both plans, so they do not change the break even.
Permits for the circuit in Salt Lake City
Changing plans needs no permit, but wiring a new tub or sauna does. Salt Lake City Building Services says no one may make any installation or alteration to an electrical system without a permit. If you own and live in the home as your primary residence, you can pull it yourself by submitting an Owner Builder Certification; rental property requires a licensed contractor. Small projects go through a quick turnaround queue meant to finish in 1 to 3 business days, and unpermitted work can bring a red tag, a double fee and eventually a Certificate of Noncompliance on the title. A sauna structure under 200 square feet on a residential lot is exempt from the building permit, but its wiring is not.
Worked example: one household, two plans
Take a Salt Lake City home that adds a 6 kW barrel sauna, used for an hour four times a month, and suppose its 4 kW hot tub heater runs about 60 hours a month in winter. That is 24 kWh for the sauna and 240 kWh for the tub, 264 kWh in all. On the standard rate, every added kWh lands above 400 and costs 11.0852 cents: about $29.26 before riders. On time of use with the tub heating off peak and the sauna used on Saturday afternoons, all 264 kWh cost 6.6111 cents: about $17.45. Switch the sauna to Tuesday evenings and its 24 kWh cost 29.7498 cents, raising the total to about $23.01, still cheaper because the tub dominates. Let the tub heat freely through weekday evenings too, putting a fifth of its hours on peak, and the time of use bill climbs to about $34.11, more than the standard rate.
Related guides
- What a sauna costs to run
- 120 V plug and play vs 240 V hot tubs
- Sauna heater breaker and wire size
- Backyard sauna permits and the 200 square foot rule by city
- NV Energy time of use with a hot tub, sauna or cold plunge in Las Vegas and Reno
Frequently asked questions
What are Rocky Mountain Power's peak hours in Utah?
On the Schedule 1 Time of Use Option, on peak is 6 p.m. to 10 p.m. Monday through Friday, except holidays. Every other hour, including all weekend hours, is off peak.
Is time of use cheaper for a hot tub in Utah?
Only if the tub, and the rest of the house, keeps on peak use low. Against the standard rate's upper block, time of use comes out ahead when less than about 19 percent of the added kWh fall in the 6 to 10 p.m. weekday window.
How much does a sauna session cost on Rocky Mountain Power?
A 6 kW heater at full draw uses 6 kWh an hour. In winter that is about 67 cents at the standard upper block, about $1.78 on peak on time of use, or about 40 cents off peak, before riders of roughly 13 percent.
What are Rocky Mountain Power's 2026 Utah residential rates?
Schedule 1, per the price summary in effect September 25, 2026: $12 a month for a single family home, then 9.8332 and 12.5263 cents per kWh in June through September and 8.7020 and 11.0852 cents in October through May, with the higher price above 400 kWh.
How long do I have to stay on time of use?
The Time of Use Option has a one year minimum term.
Do I need a permit to wire a hot tub in Salt Lake City?
Yes. Salt Lake City requires a permit for any installation or alteration of an electrical system. An owner occupant can pull it with an Owner Builder Certification; rentals require a licensed contractor.
Are holidays off peak?
Yes. The on peak window excludes holidays listed in the tariff, so those days are off peak all day.
Keep reading
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