QuickCalc

Electricity Cost Calculator

Estimate the cost of electricity used (kWh × tariff).

Reviewed by The QuickCalc Editorial Team · Last updated · About our methodology

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Result

Total cost
R1 440,00

Inputs & results at a glance

Updates live as you change the form above.

ItemTypeValue
Units usedInput450 kWh
Cost per kWhInputR3,20
Total costResultR1 440,00

About this calculator

Total cost = units (kWh) × tariff (R/kWh). Wh values are converted to kWh before pricing.

Electricity in South Africa is billed per kilowatt-hour (kWh) and the rate you pay depends on your municipality, your tariff structure and, in many areas, how many units you've already used in the month. This calculator gives you an instant estimate of total cost using the simple formula Total = Units (kWh) × Cost per kWh.

Most household tariffs are inclining block tariffs, meaning the per-kWh price rises once you exceed certain monthly thresholds. To get the most accurate result, use the average rate from your latest electricity bill or your municipality's published tariff schedule. As a rough guide, residential rates currently sit between roughly R2.50 and R4.00 per kWh in 2024/25.

Use this calculator to budget your monthly electricity, work out what a specific appliance costs to run (multiply its kW rating by the hours used to get kWh) or compare scenarios such as switching to gas, solar PV or a heat pump. Geysers, electric ovens, pool pumps and tumble dryers are typically the largest household consumers.

How to use it

  1. 1Enter the kWh used. From your meter reading or appliance rating × hours.
  2. 2Enter your tariff. Use the rand-per-kWh figure from your bill.
  3. 3Read the total cost. The cost in Rand for the consumption entered.

How it works

Electricity in South Africa is billed per kilowatt-hour (kWh) — one kilowatt of power drawn for one hour. The calculator multiplies the number of kWh you enter by the rand-per-kWh tariff to give you a total cost. If you are estimating the cost of running a specific appliance, work out its kWh consumption first: appliance rating in kilowatts × hours used = kWh. A 2 kW kettle boiled for 15 minutes uses 2 × 0.25 = 0.5 kWh.

Most South African households pay an inclining block tariff, meaning the price per kWh rises once you exceed set monthly thresholds (typically around 350–600 kWh depending on your municipality). For quick estimates use the average rate from your latest bill; for larger appliances that push you into a higher block, use the marginal (highest) rate you'll actually pay. Geysers, tumble dryers, pool pumps, electric ovens and underfloor heating are the biggest household consumers and are usually where solar, heat-pump or gas savings pay back the fastest.

Formula

Total cost = Units used (kWh) × Cost per kWh

Units used = kWh consumed; Cost per kWh = your effective tariff in Rand (check your latest bill or municipal tariff schedule).

Worked examples

600 kWh at R2.80/kWh

Total = R1,680 for the month.

3 kW geyser running 4 hours/day for 30 days at R3.10/kWh

Consumption = 3 × 4 × 30 = 360 kWh. Cost = R1,116/month just for hot water.

Frequently asked questions

What's the average South African electricity tariff?

Roughly R2.50–R4.00 per kWh in 2024/25, depending on your municipality and which block of the inclining block tariff you're in. Higher-use households pay closer to R4.00 per kWh on their marginal usage.

How do I find my exact tariff?

Check your latest electricity bill for the c/kWh figure, or download your municipality's published tariff schedule. Prepaid customers can divide the rand cost of a top-up by the units received to get an effective rate.

How do I convert an appliance to kWh?

Multiply the appliance's power rating in kilowatts by the hours used. A 2 kW heater running for 3 hours uses 6 kWh. A 1.2 kW dishwasher running for 1.5 hours uses 1.8 kWh.

What is an inclining block tariff?

A pricing structure where the first block of units each month is cheaper and the price per kWh rises once you cross monthly thresholds. It penalises high-use households.

Does this include the fixed monthly service charge?

No. Some tariff structures include a fixed daily or monthly service fee on top of the per-kWh charge. Add that in separately for a full picture.

Which appliances typically use the most?

Electric geysers, tumble dryers, electric ovens, pool pumps and underfloor heating are the biggest household consumers. See our guide on cutting your electricity bill for practical savings.

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