One of the biggest benefits of using a bidet toilet seat is reducing the amount of toilet paper one consumes.  Toilet paper is not only expensive to buy for a typical family, but its production is also very costly for the environment.  Washing with a bidet seat after using the bathroom can dramatically reduce, or even eliminate, the need for wiping with toilet paper.  So if using a bidet toilet seat can help save money on toilet paper, how much does the bidet seat itself cost to operate?

GFCI Outlet

Electricity Cost

Bidet seats in the US run on 110V electricity to power their onboard water heaters, seat warmers, and other functions.  The seat warmer and water heater can both be adjusted to various temperatures and the amount of electricity used can be greatly affected.  For example, a single user of a bidet seat that does not turn on the seat warmer and sets the water temperature to low will consume significantly less power than a family of four that uses the highest temperature settings.  Newer bidet models that utilize tankless water heating systems and energy saving functions will reduce their electrical draw even more. Due to all these variables, the actual cost of operating a bidet toilet seat can vary greatly from user to user.

Brondell Swash 1000

The chart below approximates the electrical costs of operating a Brondell Swash 1000 for a family of four with the seat warmer and water temperature set on high 24/7.  It assumes roughly 20 minutes of washing and drying each day with the power saving function turned OFF.   

High usage scenario

Cost per day: $.18

Cost per month: $5.40

Cost per year: $65.70

Given the assumptions above, this chart represents the high-end of electrical costs.  With fewer users and the power saving function turned ON, the seat warmer would be turned low during periods of non-use and the annual cost of would closer to $20 – significantly lower.  With its power saving function and tankless water heating system, the Brondell Swash 1000 is one of the most energy efficient bidet toilet seats you can buy. 

Low usage scenario

Cost per day: $.06

Cost per month: $1.80

Cost per year: $21.90

Brondell Swash 1000 Spray

Water Cost

Bidet toilet seats wash users with a small, aerated water stream.  The flow rate is approximately .5 liters/minute and with a 1 minute wash, this equates to .5 liters (.13 gallons) per “use.” Considering that older toilets use 3.5 gallons per flush, while newer toilets use 1.6 gallons, the amount of water used by the bidet toilet seat is minimal in comparison.  Assuming a high usage of 20 minutes of washing per day, this results in about 10 liters (2.64 gallons) of water used each day.  Given an average national cost of $.002 for every gallon of tap water, the annual water cost of a bidet toilet seat with high usage is a meager $1.93.

Conclusion

As explained above, the main factor driving the operating cost of a bidet toilet seat is the electrical draw.  User settings can have a big impact on the amount of electricity a bidet seat actually consumes.  If we take the average of the two scenarios above and add in the water cost, the approximate cost of operating a bidet toilet seat is about $.12 per day, or about $45.73 per year.