Ontario Electricity Explained Ontario • Electricity
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Time‑of‑Use vs Tiered vs Ultra‑Low Overnight – Cost Comparison

Updated 2026‑04‑22

Ontario households can choose between three regulated electricity pricing plans: Time‑of‑Use (TOU), Tiered, and Ultra‑Low Overnight (ULO). Each plan rewards different usage patterns, and the cheapest option depends entirely on when and how your household uses electricity.

This guide provides a clear, practical comparison of all three plans using real‑world examples, typical household patterns, and plain‑English explanations. It is designed to help you understand which plan fits your lifestyle — not just which one has the lowest rate on paper.

1. Quick Overview of Each Pricing Plan

Time‑of‑Use (TOU)

Electricity prices change depending on the time of day and day of the week. Weekends and holidays are off‑peak all day.

Best for: households that can shift flexible loads (laundry, dishwashers, EV charging) to off‑peak hours.

Tiered Pricing

You pay one rate up to a monthly kWh threshold, and a higher rate above it. Timing does not matter.

Best for: steady, predictable usage that stays mostly within the lower tier.

Ultra‑Low Overnight (ULO)

Includes a deeply discounted overnight rate, a mid‑range daytime rate, and a higher on‑peak evening rate.

Best for: EV owners, night‑shift households, or anyone who can shift significant usage to overnight hours.

2. How These Plans Affect Your Bill

All three plans use the same total kWh, but the cost changes depending on:

  • When you use electricity (TOU and ULO)
  • How much you use (Tiered)
  • Your household’s daily routine
  • Whether you have flexible loads like EV charging or laundry

Delivery charges, regulatory charges, and the Ontario Electricity Rebate are the same regardless of plan. Only the energy charge changes.

3. Usage Scenarios: Which Plan Wins?

Below are simplified examples to illustrate how each plan behaves. These are not exact bill calculations — use the calculators linked above for precise comparisons.

Scenario A: Daytime‑heavy household

Examples: work‑from‑home, retirees, families with young children.

  • High usage between 11 a.m. and 7 p.m.
  • Limited ability to shift laundry or dishwasher cycles.
Most likely cheapest: Tiered Why: TOU and ULO charge more during daytime and early evening hours.

Scenario B: Evening‑heavy household

Examples: 9‑to‑5 workers, students, typical family routines.

  • Most usage between 6 p.m. and 10 p.m.
  • Some flexibility for laundry or dishwashers.
Most likely cheapest: TOU Why: Off‑peak and mid‑peak periods can offset evening usage if flexible loads are shifted.

Scenario C: Overnight‑heavy household

Examples: EV owners, shift workers, homes with electric water heaters on timers.

  • Significant usage between midnight and 6 a.m.
  • EV charging or large appliances run overnight.
Most likely cheapest: ULO Why: The overnight rate is dramatically lower than TOU or Tiered.

Scenario D: Low‑usage household

Examples: condos, small apartments, single‑occupant homes.

  • Low total monthly kWh.
  • Usage spread evenly across the day.
Most likely cheapest: Tiered Why: Most usage stays within the lower tier.

4. Strengths and Weaknesses of Each Plan

Plan Strengths Weaknesses
TOU Rewards shifting usage; predictable weekend rates; good for moderate flexibility. Daytime usage can be expensive; requires some scheduling.
Tiered Simple; timing doesn’t matter; good for steady usage. High‑usage months can push you into the higher tier.
ULO Extremely cheap overnight rate; ideal for EVs and timers. Evening on‑peak rate is higher; not ideal for families with early‑evening peaks.

5. How to Choose the Best Plan for Your Home

Choosing the right plan comes down to three questions:

1. When do you use most of your electricity?

If your peak is daytime or early evening, Tiered may be better. If you can shift usage, TOU or ULO may win.

2. Do you have flexible loads?

Dishwashers, laundry, EV charging, pool pumps, and dehumidifiers can all be shifted to cheaper periods.

3. Do you use more or less than the Tiered threshold?

Staying under the threshold makes Tiered attractive. Going over it frequently reduces its advantage.

6. Tools to Compare Plans Accurately

For a precise comparison based on your actual usage, try:

These tools let you enter your own usage patterns and see how each plan performs.

7. Switching Plans Is Free and Easy

You can switch plans once per billing cycle through your utility. Many households experiment for a few months to see which plan works best.

There is no penalty for switching, and you can switch again if your routine changes.