How Slab Rates Work in India: Telescopic vs Non-Telescopic Tariffs Explained

In India, electricity billing is not charged at a single flat rate per kilowatt-hour (kWh). Instead, State Electricity Regulatory Commissions (SERCs) enforce tiered slab tariffs designed to encourage conservation and provide affordable lifeline power to low-income households.

However, many consumers are surprised when a small increase in consumption results in an unexpectedly massive bill. The reason often lies in whether your state follows a Telescopic or Non-Telescopic tariff structure.

1. What is a Telescopic Tariff? (The Progressive Model)

In a telescopic tariff, your total consumption is split incrementally across each individual slab bracket. Every consumer gets the benefit of the lower slabs for the first chunk of units, regardless of their total consumption.

Example: Consuming 250 Units in a Telescopic System

Suppose the tariff order specifies:

• 0 – 100 units: ₹3.50 / unit
• 101 – 200 units: ₹5.50 / unit
• 201 – 300 units: ₹7.00 / unit

If your meter records 250 units, your energy charge is calculated as:

1. First 100 units: 100 × ₹3.50 = ₹350
2. Next 100 units (101 to 200): 100 × ₹5.50 = ₹550
3. Remaining 50 units (201 to 250): 50 × ₹7.00 = ₹350

• Total Energy Charge: ₹350 + ₹550 + ₹350 = ₹1,250

States like Maharashtra (MSEDCL), West Bengal (WBSEDCL), and Karnataka (BESCOM) broadly use telescopic structures for domestic categories.

2. What is a Non-Telescopic Tariff? (The Cliff-Edge Model)

In a non-telescopic tariff, once your total consumption crosses a specific threshold, all your units are billed at the higher slab rate, or you lose the entire subsidy from the ground up!

The Infamous "1 Unit Penalty"

Consider a tariff where:

• Up to 200 units: ₹3.00 / unit

• Above 200 units: ₹6.00 / unit for all units

• If you consume 200 units: 200 × ₹3.00 = ₹600

• If you consume 201 units: 201 × ₹6.00 = ₹1,206

A single extra unit burned cost the consumer ₹606 more! Certain DISCOMs in Uttar Pradesh (UPPCL) and historical tariffs in Tamil Nadu (TANGEDCO) have utilized variants of this non-telescopic system.

3. Other Hidden Components on Your Indian Power Bill

Beyond energy charges, your final monthly bill includes:

1. Fixed Charges (Sanctioned Load): A monthly fee charged per kilowatt (kW) of sanctioned load (e.g., ₹50 to ₹120 per kW), regardless of whether power was consumed.
2. FPPCA (Fuel Price Adjustment): A floating variable cost per unit reflecting fluctuating coal and gas procurement costs by power generation plants.
3. Electricity Duty & Tax: A state government surcharge ranging between 5% to 15% applied to the net energy charge.

4. How to Prevent Sudden Tariff Spikes

• Monitor Your Meter Near Billing Day: If your monthly billing cycle is approaching 200 or 400 units, reduce heavy appliances (geysers, ACs) for the last 48 hours.
• Check Your Sanctioned Load: If your peak load exceeds your sanctioned limit, DISCOMs levy hefty penalties (up to 2× fixed charges).
• Use Our Calculator: Use our Universal Electricity Bill Calculator to simulate your state's exact tariff order before your bill arrives!