Eligibility for Rate M

Rate M applies to your contract if your maximum power demand has been at least 50 kilowatts (kW) during a consumption period included in the last 12 monthly periods.

This information has been simplified. For more details about Rate M, consult Section 1 of Chapter 4 of the Electricity Rates [PDF 4.83 MB], approved by the Régie de l’énergie.

We will be launching a pilot project on dynamic pricing for Rate M customers. If you would like more information about this Flex rate and whether it could apply to your business, please call us at 1 800 463‑99001 800 463‑9900 or write to us at business@hydro.qc.ca.

Structure of Rate M

Billing for Rate M includes the following:

  • An amount for the energy in kilowatthours (kWh) consumed during the period in question. Two different prices apply depending on the amount of energy consumed:
    • A price for the first 210,000 kWh
    • A lower price for the remaining consumption
  • An amount for the billing demand in kilowatts (kW).

Rate M is a monthly rate, which means the first-tier consumption limit, and the amount billed as demand, and the minimum charge are based on a 30‑day period.

If applicable, the following may lower your bill:

Credit for supply at medium or high voltage

Hydro‑Québec’s rates assume that electricity will be supplied at low voltage. If you have equipment to step down the voltage of the electricity delivered to you or if you use electricity at medium or high voltage, that means reduced costs for Hydro‑Québec. In return, you receive a monthly credit on your demand charge. The credit is determined according to the supply voltage.

Adjustment for transformation losses

Hydro‑Québec bills you only for the electricity you use. This means it absorbs the transformation losses associated with electricity delivery. If metering occurs before transformation, the electricity billed will include energy lost during transformation that does not reach the customer. So that you do not pay for energy losses, Hydro‑Québec grants an adjustment on the billing demand.

See Helping you understand your electricity rate

Rate M prices in effect

Breakdown of billing

  • Price of energy
    • First 210,000 kWh 5.03¢/kWh
    • Remaining consumption 3.73¢/kWh
  • Price of power $14.58/kW 

Applicable in certain cases

  • Credit for supply at medium or high voltage
    • Voltage of 5 kV to less than 15 kV $0.612/kW
    • Voltage of 15 kV to less than 50 kV $0.981/kW
    • Voltage of 50 kV to less than 80 kV $2.190/kW
    • Voltage of 80 kV to less than 170 kV $2.679/kW
    • Voltage of 170 kV or more $3.540/kW
  • Adjustment for transformation losses 17.76¢/kW 

If little or no electricity is used, a minimum charge is billed. It is $12.33 per month (30 days) when single-phase is delivered or $36.99 per month when three-phase is delivered.

Rates in effect as of April 1, 2019. This table does not replace the Electricity Rates document in any way whatsoever.

How to read your Rate M bill

Switching to another rate

Switch to Rate G9

If your load factor is usually below 30%, Rate G9 may be better for you, because, at this rate, energy carries greater weight than power.

For more information, contact your commercial officer or designated agent. Our Business customer services can also be reached at the numbers in the Contact us section.

Comparison of bills calculated at Rate M and Rate G9

The following table compares four customers with a billing demand of 140 kW, but different load factors.

Case Load factor Energy consumed
Billed at
Rate G9
Billed at
Rate M
Customer 1 10% 10,080 $1,608 $2,548
Customer 2 20% 20,160 $2,624 $3,055
Customer 3 30% 30,240 $3,640 $3,562
Customer 4 40% 40,320 $4,656 $4,069

Billing for a 30‑day consumption period with no discount for supply at medium or high voltage or adjustment for transformation losses (rates in effect April 1, 2019, excluding taxes).

Details on Rate G9

Switching to a large power rate

If your minimum billing demand is 5,000 kW or more, Hydro‑Québec will automatically switch your contract to a large‑power rate: Rate L, if your contract is related to an industrial activity, or Rate LG, in other cases.

If your minimum billing demand is just under 5,000 kW, it may be better for you to switch to Rate L or LG. Discuss your options with your commercial officer or designated agent. Our Business customer services can also be reached at the numbers in the Contact us section.

Planning any changes?

If you plan to buy new equipment, extend your business hours or enlarge or renovate your facility, your use of electricity could increase and it could then be to your advantage to switch to Rate L or LG, or your contract could be switched automatically. Discuss your options with your commercial officer or designated agent. Our Business customer services can also be reached at the numbers in the Contact us section.

Other rates or rate options

If you have a Rate M contract, the following offerings may be of interest to you.

  • Industrial Revitalization Rate
    This new rate, in effect April 1, 2019, allows Rate M customers whose contract is mainly related to an industrial activity to benefit from an advantageous price to return unused production capacity to operation or to convert an industrial process that is currently powered by fossil fuel to electricity.
  • Running-in of new equipment by medium‑power customers
    If you’re putting new equipment or a new facility into service, your power demand could increase for a few months until your operations have been optimized. Under this option, you can be temporarily exempt from certain rate conditions applicable to power billing.
  • Equipment testing by medium‑power customers
    If you have to run short tests after adding new equipment or modifying or optimizing existing equipment, your power demand may rise temporarily. Under this option, you don’t have to pay for the excess power used during the test period(s).
  • Additional electricity option for medium‑power customers
    Under this rate option, you can use electricity beyond your normal consumption to fill a short-term order or meet an exceptional need at a lower price for both energy and power.
  • Additional electricity option for photosynthetic lighting
    If the electricity you consume is in whole or in part for photosynthetic lighting (greenhouse growing) and your maximum power demand has been at least 300 kilowatts (kW) during a consumption period included in the 12 consecutive monthly periods preceding the date of the sign-up request, this rate may be advantageous for you.
  • Interruptible electricity options for medium‑power customers
    If you can lower your consumption at Hydro‑Québec’s request, these options offer a great opportunity for you to save on your electricity bill during the winter period.
  • Economic Development Rate
    Are you planning to build and commission a new facility with a power demand of at least 1,000 kW or to add at least 500 kW of power demand to an existing facility? This rate offers a great opportunity for you to save on your electricity bill.

Maximum power demand

Maximum power measured during a consumption period. It is the higher of the following two values: real power in kilowatts (kW), or a percentage (90% for domestic rates and small- and medium-power rates, or 95% for large-power rates) of the apparent power in kilovoltamperes (kVA).

Monthly period

Period of 30 days, which may begin on any day of the month, established by Hydro-Québec for billing purposes.


Power used by electrical equipment over a given period of time. Expressed in kilowatthours (kWh), energy is calculated as power, expressed in kilowatts (kW), multiplied by the time during which the power is used, expressed in hours (h).


Total amount of electricity supplied at a given time. Expressed in kilowatts (kW), power is the combined effect of voltage, expressed in kilovolts (kV), and current, expressed in amperes (A).

  • Low voltage: Voltage of 750 V or less.
  • Medium voltage: Voltage of more than 750 V, but less than 44 kV.
  • High voltage: Voltage of 44 kV or more.


Difference in electrical level between two points, expressed in volts (V).


Operation that involves increasing or decreasing voltage through a transformer.

Load factor (LF)

Relationship between the energy (in kilowatthours) actually consumed and the amount of energy that can be consumed by using the entire maximum power demand throughout the consumption period. The load factor indicates the utilization rate of maximum power demand for a given consumption period.

Minimum billing demand (minimum demand)

The minimum amount of power that the customer must pay for each consumption period, regardless of electricity use. The threshold is set so that you pay your share of the costs Hydro-Québec incurs to meet your power needs at all times. The minimum billing demand is determined by the conditions of each rate, as indicated in the Electricity Rates.

  • For all rates except Rate L, the minimum billing demand is automatically determined based on the previous winter’s maximum power demand.
  • Rate L customers must set their own minimum billing demand, called “contract power,” based on the amount of electricity they expect to use.

Power demand

Power a customer requires to meet energy needs at a given time. The higher the customer’s energy consumption at a given time, the higher the power demand.

Winter period

Period from December 1 through March 31 of the next year, inclusive.

Minimum charge (minimum monthly bill)

Minimum amount billable for electricity service even if little or no electricity has been used in the billing period.