1. What is an Electricity Tariff Slab & How Does It Work?
In India, retail electricity billing does not follow a single flat per-unit rate. Instead, State Electricity Regulatory Commissions (such as DERC in Delhi, MERC in Maharashtra, TNERC in Tamil Nadu, and KSERC in Kerala) establish progressive tariff slabs.
Under slab-based tariff structures, electricity is treated as an essential commodity for baseline lifeline needs (lighting, fans, basic refrigeration), while higher luxury consumption (multiple air conditioners, water heaters, EV chargers) is billed at progressively higher per-unit rates.
2. Telescopic vs Non Telescopic Slab Comparison
The most important concept in Indian power billing is whether your state's tariff schedule is telescopic vs non telescopic slab:
✅ Telescopic Slab (Most Indian States)
Your consumption is partitioned into chunks. Units in the first slab (0–100) are billed at the cheapest rate, units in the next slab (101–200) at the intermediate rate, and only remaining units in higher slabs at the highest rate. You never lose the benefit of lower slab rates for initial units.
⚠️ Non Telescopic Slab (e.g., Kerala KSEB > 250 units)
Once your total consumption exceeds a specified ceiling (such as 250 units in Kerala), the slab structure collapses into a flat tier where all units from unit 1 onwards are charged at the elevated rate, resulting in a sudden jump in the final bill.
3. How to Calculate Electricity Bill from Meter Reading
Calculating your electricity bill directly from your electric meter involves 3 quick steps:
Read the cumulative active energy number on your electronic meter screen when the 'kWh' text flashes (e.g. 5,420 kWh).
Find the previous meter reading on your last electricity bill (e.g. 5,150 kWh). Net Units = 5,420 - 5,150 = 270 units.
Multiply units within each slab, add fixed load charges, fuel adjustment surcharges, and state electricity duty.
4. The 5 Core Components of an Electricity Bill
Your total payable electricity bill is the sum of five distinct components:
1. Energy Charges (EC)
The primary charge based on active electricity consumed (in kWh units), calculated by multiplying units consumed within each slab by the approved slab rate.
2. Fixed / Demand Charges (FC)
A mandatory recurring charge based on your sanctioned connected load (in kW). It pays for maintaining the grid, transformers, and distribution infrastructure even if zero energy is consumed during a month.
3. Fuel Price Adjustment Surcharges (FAC / FPPPA / PPAC)
A quarterly adjustment reflecting variances in coal, fuel, and transmission costs. Usually ranging from ₹0.20 to ₹1.20 per unit.
4. State Electricity Duty Tax
State government tax applied as a percentage on the subtotal of Energy Charges and Fixed Charges. Ranges from 3% to 21% depending on the state (e.g. Maharashtra 16%, Delhi 5%, Gujarat 15%).
5. State Government Subsidies (Deductions)
Direct bill credits or waivers provided by state welfare schemes, such as Delhi's 200 free units, Karnataka's Gruha Jyothi, Punjab's 300 free units, or Tamil Nadu's 100 free units bi-monthly.
5. State Free Electricity & Subsidy Schemes Overview
| State | Scheme Name | Subsidy Benefit | Eligibility Rule |
|---|---|---|---|
| Delhi | DERC Power Subsidy | 100% Free up to 200 units; 50% rebate up to 400 units | Opt-in domestic consumers |
| Punjab | PSPCL Zero Bill | 300 Free Units / month (600 bi-monthly) | All domestic meter connections |
| Karnataka | Gruha Jyothi Scheme | Up to 200 Free Units / month | Registered Seva Sindhu users within entitlement average |
| Tamil Nadu | TANGEDCO 100 Units | First 100 Units Free Bi-Monthly | All LT-1A domestic consumers |
| Telangana | Gruha Jyothi TGSPDCL | Up to 200 Free Units / month | White Ration Card holders |
6. Frequently Asked Questions (FAQ)
What is a telescopic electricity tariff slab?
A telescopic tariff slab is a progressive pricing model where consumption is divided into incremental brackets. Lower units (e.g. 0-100) are charged at lower rates, and only the excess units (e.g. 101-200) are billed at the next higher tier rate. This protects moderate consumers from sudden bill spikes.
What is the difference between telescopic vs non telescopic slab billing?
In telescopic billing (used by most Indian states like Maharashtra, UP, and Delhi), each tier is charged at its respective rate regardless of total consumption. In non-telescopic billing (used for high consumers in Kerala KSEB above 250 units), crossing a consumption threshold causes all units from unit 1 to be charged at a higher flat rate.
How to calculate electricity bill from meter reading units?
To calculate electricity bill from meter reading: (1) Note the current cumulative kWh reading on your digital electricity meter, (2) Note the previous month's final meter reading, (3) Subtract previous from current (Current kWh - Previous kWh = Net Units Consumed), and (4) Apply your state's tariff slab rates, fixed charges, FAC surcharge, and electricity duty tax.
How are fixed charges calculated in electricity bills?
Fixed charges (also known as demand charges) are calculated as: Sanctioned Load (kW) × Fixed Charge Rate (₹/kW/month). For instance, if your sanctioned load is 2 kW and the fixed charge is ₹75/kW/month, your monthly fixed fee is 2 × ₹75 = ₹150, regardless of energy consumed.
What is Fuel Adjustment Charge (FAC / FPPPA)?
FAC (Fuel Adjustment Charge) or FPPPA (Fuel Price and Power Purchase Adjustment) is a variable per-unit surcharge reflecting quarterly fluctuations in power procurement and coal/gas prices incurred by the distribution utility.
Which Indian states offer free electricity or zero bill schemes?
Delhi (100% subsidy up to 200 units), Punjab (300 units free per month), Karnataka (up to 200 units free under Gruha Jyothi), Tamil Nadu (first 100 units free bi-monthly), and Telangana (200 free units under Gruha Jyothi) offer government electricity subsidies.
Calculate Your State Bill with Live Tariff Slabs
Select your state, enter your units consumed, and get an immediate itemized receipt.