During the long period of load shedding, most households used fewer units and stayed within the cheaper tariff bands. Now that power is more stable, usage has increased, and many customers are moving into higher tariff bands.
Below is a simple explanation of how Zesco residential tariffs work.
Zesco uses four progressive tariff bands. This means electricity becomes more expensive as you use more units in a month, up to and beyond 400 units.
The tariff bands are:
0–100 units: K0.35 per unit
101–200 units: K1.00 per unit
201–400 units: K2.42 per unit
Above 400 units: K3.45 per unit 
The bands are applied step by step as illustrated below:
BAND 1:
First 100 units
100 × K0.35 = K35
BAND 2:
101–200 units
100 × K1.00 = K100.
That means K135 will give you 200 units.
BAND 3:
201–400 units
200 × K2.42 = K484
That means you need to spend K619 for 400 units (K135 for the first 200 units and K484 for units over 200 and up to 400).
BAND 4: Any unit above 400 is charged at K3.45 per unit.
Key Point
You can use up to 400 units in a month and spend about K619 before reaching the most expensive tariff. Once you go above 400 units, electricity becomes much more expensive.
Practical Examples
If you buy electricity worth K300, you will stay below 400 units. If you buy electricity worth K600, you will be close to 400 units. If you buy electricity worth K800, part of your purchase will be charged at K3.45 per unit.
Understanding these tariff bands helps explain why units now finish faster than before.
