Start with the units, not just the amount paid
After buying a prepaid token, find the amount paid in rand and the number of units issued in kilowatt-hours (kWh). These are different things. The token supplies a number of kWh, while the amount paid may also cover other charges.
Check the meter number and purchase date too. If the meter number is wrong, do not enter the token into another meter. Contact the vendor or electricity supplier using their official support channel.
Look for deductions before the energy amount
Some receipts show deductions separately. The description depends on the supplier and vendor. You might see a service charge, a utility charge or an amount recovered against an outstanding account. Not every customer has the same deductions.
For example, the City of Cape Town's Domestic prepaid tariff for 2026/27 includes a Services and Wires Charge recovered through purchases at R2.46 per day since the last purchase. The City can also recover qualifying outstanding municipal debt through prepaid purchases. If a receipt looks unusual, ask the supplier what each line means. The City's prepaid purchasing page explains its debt recovery process.
Example: R500 bought in Cape Town
Suppose a City of Cape Town Domestic customer pays R500 after seven days without a purchase. Seven days at R2.46 comes to R17.22 in Services and Wires charges. That leaves R482.78 for electricity, assuming no debt recovery or other deductions.
For the first 600 kWh purchased in the month, the City's Domestic energy tariff from 1 July 2026 is R4.1379 per kWh, including VAT. At that rate, R482.78 buys approximately 116.67 kWh, provided the entire purchase stays in that first block.
The total R500 divided by 116.67 kWh works out to about R4.29 paid per unit on this particular receipt. That is not the published energy tariff. It includes the seven days of recovered fixed charges. Someone with a different number of chargeable days can get a different effective figure.
Compare receipts in the right way
- Check the same supplier and tariff. City of Cape Town, Eskom and other municipalities can charge different rates. Even two City households may be on different residential tariffs.
- Separate energy and deductions. Divide the amount actually spent on energy by the units issued if you want to compare the energy price. Divide the full payment by the units if you want the total paid per unit on that receipt.
- Check purchases earlier in the month. Cape Town counts monthly prepaid purchases towards tariff blocks. Buying twice does not restart the cheaper block. Units above the first-block threshold can cost more.
- Check VAT carefully. The Cape Town 2026/27 rates quoted here include VAT. Do not subtract VAT a second time when using those rates in a calculation.
Keep two or three receipts and compare their dates, units, deductions and tariff names. If you cannot identify a charge, ask the supplier before assuming the vendor made a mistake.
Use a calculator with your own details
HowMuchSA's prepaid electricity calculator lets you enter the payment amount, unit rates, electricity bought earlier in the month and estimated deductions. It also has an optional City of Cape Town Domestic 2026/27 example. It cannot see your account, check a token or confirm your tariff.
For a comparison of Domestic, Home User and Lifeline tariffs, see the Cape Town R500 electricity guide.
What this guide does not tell you
A receipt calculation cannot confirm your tariff eligibility, debt balance or why a particular deduction was made. Some vending systems round amounts or present their line items differently. These examples cover City-supplied Domestic customers, not everyone living in Cape Town. If your meter is supplied by Eskom, another municipality or a private reseller, use the rates and charges from that supplier.
Official sources
- City of Cape Town: 2026/27 residential electricity tariffs (checked 13 October 2026)
- City of Cape Town: Buy prepaid electricity and debt deductions (checked 13 October 2026)
- City of Cape Town: How monthly prepaid tariff blocks work (checked 13 October 2026)
These calculations are for information only, not a quote or account statement. Check your actual receipt and supplier terms before making a payment decision. You can read our editorial approach or suggest a correction.