Tiered Electricity Bill Calculator

About this calculator

Many utilities bill electricity using an increasing block tariff: the first block of kilowatt-hours (kWh) used each billing period is charged at a lower rate, and any usage beyond that threshold is billed at a higher rate for the next block. The structure is designed to keep basic usage affordable while charging more for heavier consumption, encouraging conservation.

The total bill is the sum of each block's usage multiplied by that block's rate, not the full usage multiplied by one flat number, which is why a bill can jump disproportionately once a household crosses into the next tier. This calculator takes your total kWh used along with each tier's rate and threshold and returns the total bill, split correctly across both blocks — useful for households trying to estimate a bill before it arrives or understand exactly what pushed a bill higher than expected.