When Is the Best Time to Buy Prepaid Electricity? (2026 SA Guide)
If you’ve ever asked, “When is the best time to buy prepaid electricity?” - you’re not alone.
In South Africa, the answer could save you hundreds every month. Most municipalities use inclining block tariffs, which means your electricity gets more expensive the more you use in a single month.
But here’s the good news: you can cut your effective rate by up to 40% just by timing your top-ups correctly.
How Block Tariffs Work
Cities like Johannesburg, Cape Town, and Tshwane divide monthly electricity usage into pricing blocks:
- Block 1 (0–350 kWh): Cheapest rate (e.g., R2.20/kWh)
- Block 2 (351–600 kWh): Higher rate (e.g., R3.10/kWh)
- Block 3+ (601+ kWh): Most expensive (e.g., R4.00+/kWh)
Your usage resets on the 1st of every month—not when you buy tokens.
The Smart Strategy: Buy Early, Stay in Lower Blocks
Most people wait until their credit runs low—often in the last week of the month. By then, they’ve already crossed into Block 3 or 4, so every new kWh costs significantly more.
Instead, follow this simple rule:
- Buy your electricity on the 1st (or within the first 3 days) of the month
- Split large purchases into two early top-ups to avoid jumping blocks
- Track daily usage using your municipality’s app or SMS alerts
Real Savings Example
A household using 500 kWh/month in Johannesburg:
- Bad timing (buys late): Pays R3.55/kWh for most units → R1,775 bill
- Smart timing (buys on the 1st): Stays in Block 1 & 2 → R1,320 bill
That’s a R455 monthly saving - over R5,400 per year - with no change in lifestyle.
Municipal Tips
- Cape Town: Use the “Electricity Usage” tool in the CoCT app to monitor your block in real time.
- Johannesburg: Avoid buying after the 25th—most users are already in Block 4 by then.
- Tshwane: Tariff resets at midnight on the 1st—set a phone reminder!
For a full breakdown of how rates compare across cities, see our guide to municipal electricity tariffs in South Africa.
Updated 2 February 2026.
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Build Your Own →Frequently Asked Questions
The best time is on the 1st of the month (or within the first 3 days), when your usage block resets. This ensures you pay the lowest possible rate per kWh.
Most major metros—Johannesburg, Cape Town, Tshwane, and eThekwini—do. Smaller towns may use flat rates, so always check your local tariff schedule.
No. Blocks reset automatically on the 1st of each month based on calendar usage, not your purchase date.
Use your municipality’s official app—like “CoCT” for Cape Town or “Joburg Connect” for Johannesburg—or SMS your meter number to their service line.
Only if you buy early. Buying a large amount on the 28th still puts you in a high block. Timing matters more than volume.
Yes. With enough solar generation—especially with high-output systems like the 3D Solar Panel Tower—you can reduce or eliminate grid dependence and never pay Block 4 rates again.