Why does R200 of prepaid electricity buy fewer units some months?
Inclining block tariffs, monthly resets, arrears deductions and recent municipal increases all change how many kWh you actually get. Here's how to read your token slip and budget around the cycle.
Why R200 of prepaid buys fewer units some months
If you've ever bought R200 of prepaid electricity at the start of the month and got a comfortable number of kilowatt hours, then bought another R200 two weeks later and watched the units shrink, you're not imagining it.
1. Inclining Block Tariffs (IBT) reset every month
Most South African municipalities and Eskom-direct customers are on an inclining block tariff — the more kWh you use in a month, the higher the rand-per-kWh rate becomes. The block counter resets on the first day of each month.
Your first purchase of the month buys cheap units. Once you cross the block threshold (often around 350–600 kWh), every kWh you buy for the rest of that month is at the higher block rate.
2. Arrears recovery and service charges
Many municipalities recover other municipal debts (water, refuse, rates) from your prepaid electricity purchases. The percentage and the cap differ by municipality. The deduction is shown on your token slip — always check it.
3. Tariff increases happen mid-year
Eskom's annual tariff increase usually takes effect on 1 April for direct customers and on 1 July for municipal customers. If you compare May to June, you may be paying a lower rate; June to August, a much higher one.
4. The fix
- Buy in larger amounts at the start of the month — you'll spend more time inside the cheap block. - Use our [rand-to-kWh calculator](/calculator) to see exactly where you are in the block right now. - Check your municipality on the [tariffs page](/tariffs) to confirm the block boundaries and rates that apply to you, not the national average.
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