Every summer, millions of households across Pakistan open their electricity bill and stare in disbelief. "Pichhle mahine 15,000 tha, is mahine 28,000 kaise ho gaya?" Here are the nine reasons it happens — most of them fixable, most of them diagnosable in ten minutes with the bill in your hand.
1. You crossed a slab
The biggest single reason. Domestic slabs jump at 100, 200, 300, 400, 500, 600 and 700 units. Every unit above a slab costs more than the units below it. Cross 200 units and you can pay 40% more per unit for the whole month, not just the marginal units.
Check: Compare this month's units against last month. Is this month 210 vs last month 190? That's a slab jump, not a mistake.
Fix: Track your daily meter reading. Walking to the meter each morning and jotting the number takes 30 seconds and prevents almost every surprise.
2. You lost protected status
Protected consumers (≤200 units for 6 consecutive months on a single-phase connection) pay the lowest first-slab rates in the country. Cross 200 units even once and the entire month re-prices at unprotected rates — plus FPA and QTA that protected consumers don't pay. That's often the biggest single reason for a shock bill.
Check: Look at the "Tariff" line. If it says A-1a Protected last month and A-1a Unprotected this month, you know why.
Fix: Once you're unprotected, you need 6 straight months under 200 units to earn protection back. Deep guide: our [protected vs unprotected explainer](/protected-vs-unprotected).
3. Fuel Price Adjustment spike
FPA is charged per unit and varies month to month. In peak LNG months (December–February) it can hit Rs. 4–6 per unit; on 400 units that's Rs. 1,600–2,400 extra before GST. Add 18% GST on top and you're at Rs. 2,000–2,900.
Check: Find the FPA line on your bill. Divide by your units to get the per-unit rate. Cross-reference with NEPRA's published rate for your DISCO for the relevant month.
Fix: Consume fewer units, or stay in the protected slab (protected consumers pay zero FPA). See our [FPA tracker](/fpa-tracker) and [FPA blog post](/blog/understand-fuel-adjustment-charges).
4. Meter fault
Old or damaged meters can over-record — sometimes by 5–15%. Meters older than 12–15 years drift more.
Check: Note the meter reading at 8 AM, then at 8 AM the next day. That's your 24-hour consumption. Compare against a rough estimate (AC hours × 1.5 kW + fridge 3 kWh + lights + fans + other). If the meter reading is 20%+ higher than your estimate, request a check.
Fix: Request a free meter test at your local DISCO SDO. If confirmed faulty, the meter is replaced and recent over-billing is refunded.
5. Detection / line-loss catch-up
DISCOs occasionally bill you for "detected" losses on your feeder or from an alleged meter tamper. These can be huge — Rs. 50,000+ in a single line.
Check: Ask for the calculation in writing at your SDO. Any detection bill without a proper audit report can be disputed.
Fix: File a written objection within 30 days, escalate to NEPRA if the DISCO doesn't reverse it.
6. Extra AC hours
A 1.5-ton non-inverter AC pulls about 1500W. Six extra hours a day for a month adds ~270 kWh — enough to push a household from 300 to 570 units, crossing two slab boundaries.
Check: Reconstruct the month. Did you have guests? Sick relatives? A newborn? All-night AC?
Fix: Inverter AC (roughly half the wattage), higher setpoint (26°C vs 22°C saves ~25%), fans first, AC second.
7. Geyser left running
Electric geysers pull 2000–3000W. Left on 3 hours/day for a month = 180–270 kWh — often the second most expensive appliance in a Pakistani home after AC.
Check: Is the geyser switch on the "always on" side of the DB? Turn it off between uses.
Fix: Instant gas geyser if piped gas is available. Otherwise, use only when needed and turn off immediately after.
8. New appliance, old habits
Bought a new fridge, chest freezer, second AC, water pump, or dishwasher recently? Every new appliance adds a baseline. Two ACs instead of one, a chest freezer for the summer wedding season — these push you 100+ units per month higher without you noticing.
Check: List every appliance added in the last 3 months. Multiply typical daily hours by rated wattage. That is your added baseline.
Fix: Use our [appliance cost calculator](/calculators/appliance-cost) to see monthly rupee cost of each device before installing.
9. Wrong tariff category
Sometimes DISCOs mistakenly classify a domestic connection as A-2 commercial. Commercial rates are 20–30% higher per unit plus different taxes.
Check: Look at the "Tariff" line. Domestic residential should read A-1a. Anything else on a home connection is worth investigating.
Fix: Written application at your SDO with proof of residential use (utility bill of the same address, CNIC).
The 10-minute diagnostic
1. Fetch this month's bill and last month's bill from the search box at the top of this site. 2. Put them side by side. 3. Compare: units, tariff, protected/unprotected status, FPA line, QTA line, detection line. 4. Whichever line jumped the most is your culprit. 5. Use our [month-on-month comparison calculator](/calculators/comparison) to isolate the exact rupee difference per line.
Once you know which of the nine reasons applies, the fix is straightforward — and future bills stay under control.