Why is my electricity bill suddenly high?

You open the bill and it's 40% higher than last month. Before you assume the DISCOM made a mistake, here are nine reasons your bill might have spiked — in rough order of likelihood.

1. You crossed into a higher slab

In telescopic states, extra units are charged at a higher rate only at the margin — but in non-telescopic states (e.g. Kerala), crossing a slab pushes all units to the higher rate. A single hot week of AC use can do this.

2. FAC has increased

Fuel & Power Purchase Cost Adjustment (FAC or FPPCA) changes monthly. In 2023–24 many DISCOMs saw sharp FAC increases after imported coal price spikes. Check the FAC line item on your bill.

3. Estimated billing caught up

If a meter reader couldn't read your meter for a cycle, the bill might be a flat estimate. The next bill "catches up" and looks huge.

4. A new appliance was added

Geysers, ACs, induction stoves and electric water heaters are heavy hitters. A 2 kW geyser running 1 hour/day = 60 units/month.

5. Hidden standby loads

Set-top boxes, routers, TVs in standby, and phantom loads from inverters and UPS can add 30–80 units/month combined.

6. Faulty or leaking appliances

A failing compressor, blocked AC filter, or leaking geyser element will pull 2–3× the rated load.

7. Meter fault

Rare but possible. Request a meter test from your DISCOM — often free and resolved in a week.

8. Solar output dropped (if you have solar)

Dust on panels in summer, shading from new construction, or inverter faults reduce generation — your grid draw spikes.

9. Tariff revision

SERCs revise tariffs, typically in April. A 6–8% increase isn't unusual. Compare your current unit rate to the one six months ago.

Quick check: run our bill calculator with last month's units and this month's units. If the delta matches the bill difference, it's a real usage spike. If not, investigate estimated billing or FAC.