Electricity Bill Calculator

The one-unit problem

Two households in the same street. One uses 300 units in a month and pays about Rs 11,300. The other uses 301 units and pays about Rs 13,400.
One extra unit. Roughly two thousand rupees.
This is not a mistake, and it is not your DISCO overcharging you. It is how the slab system works for regular domestic consumers, and understanding it is worth more than any other single fact about your bill.

Which consumer are you?

Three categories, and the difference between them is enormous – a protected consumer pays about Rs 12 per unit all in, while a regular consumer on 600 units pays close to Rs 49.
Lifeline. Up to 100 units a month, on the lowest rates in the schedule – Rs 3.95 for the first 50 units and Rs 7.74 from 51 to 100. Lifeline consumers are also exempt from the monthly fuel charges adjustment. They get no slab benefit, so the whole bill sits at one rate.
Protected. Up to 200 units a month, with no air conditioner on the meter and a sanctioned load below 5 kW. Crucially, your consumption has to have stayed within 200 units for the preceding six months – one month above the line and you lose the status, and earning it back takes another six. Protected consumers are the only ones who get the benefit of one previous slab, meaning they are billed progressively rather than at a flat rate.
Regular. Everyone else. No slab benefit, fixed charges from 301 units upward, and the full fuel adjustment.
Your category is printed on your bill. Your DISCO decides it – you cannot select it.

The rates, as notified for CY 2026

These are the GoP Applicable Uniform rates for A-1 Residential, taken from Annex-C of NEPRA’s Decision of the Authority dated 12 January 2026. NEPRA now determines consumer-end tariffs on a calendar-year cycle, so this schedule runs through 2026.

Time-of-use metering is separate again: Rs 46.85 per unit at peak and Rs 40.53 off-peak, with a Rs 1,000 fixed charge.

 Everything else on the bill

The slab rate is one line. Four more sit on top of it, and together they add roughly a third to what you pay.
Fuel Charges Adjustment. NEPRA recalculates this every single month, based on what generating electricity actually cost against what was assumed in the tariff. It reaches your bill two months late – the adjustment for May 2026 appears on July 2026 bills. Lifeline consumers are exempt.
Quarterly Tariff Adjustment. Recalculated every three months. It can go either way; at the moment it is a credit, reducing bills issued between June and August 2026.
Electricity duty and General Sales Tax. Duty is provincial and applies to your energy and fixed charges. GST then applies to almost everything above it, including the adjustments – which is why a rise in fuel costs raises your bill by more than the fuel adjustment itself.
TV licence fee. A flat monthly amount collected on behalf of PTV, whether or not you own a television.

The number that actually matters for solar

Look at the bottom of your result: the all-in rate per unit.
At 300 units, a regular consumer pays about Rs 37.80 per unit once everything is counted, against a slab rate of Rs 33.10. At 600 units it is roughly Rs 49 against a slab rate of Rs 41.62. Above 700 units it passes Rs 56.
That gap exists because duty, GST and the adjustments all ride on top of every unit you buy. And it is the all-in rate – not the slab rate – that a solar system saves you, because every unit your roof produces is a unit you do not buy at that full loaded price.
It also explains why solar pays back faster for heavy users. A household on 250 units is displacing units worth Rs 38. A household on 900 units is displacing units worth Rs 56. Same panels, same sunlight, nearly fifty per cent more value per unit generated.

Next step

You now know what you pay per unit. The question worth asking next is how much of it solar actually removes – and the honest answer is less than most quotes suggest, because what you export is credited well below what you buy at.