Time-of-Use Electricity Rates, Explained
A time-of-use (TOU) rate charges a different price per kWh depending on the time of day and sometimes the day of the week — higher during "peak" hours of high grid demand, and lower during "off-peak" hours — so the same total usage can cost more or less depending on when it happens.
How peak and off-peak periods work
Utilities that offer TOU rates typically define a peak window (often weekday afternoons and early evenings, when overall grid demand is highest) with a higher rate, and off-peak hours (nights, early mornings, weekends) with a lower rate. Some plans add a mid-peak tier in between. The specific hours and rate difference vary significantly by utility and region.
Who tends to benefit
TOU rates tend to favor households and businesses that can shift usage — running laundry, dishwashers, EV charging, or industrial equipment during off-peak hours — away from the peak window. If your usage is concentrated during peak hours and hard to shift (a typical 9-to-5 office, for example), a flat rate may end up cheaper.
How to tell if you’re already on one
Check your bill for multiple rates per kWh at different times, or a chart showing peak/off-peak hours — if you see only a single flat rate, you’re on standard flat-rate billing instead.
Frequently asked questions
Are time-of-use rates mandatory?
It depends on the utility — some make TOU the default rate structure, some offer it as an optional plan, and some don’t offer it at all. Check with your specific utility.
Can a TOU rate save money for someone who works normal daytime hours?
It depends on how much of your usage happens during peak hours versus off-peak. If you’re home and using appliances mostly in the evening peak window, a TOU rate could cost more than a flat rate — running the numbers on your actual usage pattern is the only way to know.
Do EV owners benefit from TOU rates?
Often yes, since EV charging can usually be scheduled overnight during off-peak hours, one of the more flexible loads a household has.
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