Marginal unit price (top slab, incl. FCA & duty)
₹6.75 /unit
This is what your next unit costs once you're in the top slab — the realistic cost of running one more appliance.
Full slab-wise rates
| Slab | Rate/unit |
|---|---|
| 0–100 units | ₹2.25 |
| 101–200 units | ₹3.50 |
| 201–500 units | ₹4.80 |
| 501–∞ units | ₹6.40 |
- Billing cycle
- bi-monthly
- FCA
- ₹0.35/unit
- Verified
- 29 August 2026
Want your full bill, not just the unit price?
Open the full TNEB bill calculator →Frequently asked questions
What is the price of 1 unit of electricity in Tamil Nadu?
TNEB's residential tariff starts at ₹2.25/unit for the first slab and rises to ₹6.40/unit at the top slab, before fuel cost adjustment and electricity duty. Your actual per-unit cost depends on your total consumption, since the tariff is telescopic.
Why isn't there one single "1 unit price"?
TNEB bills residential consumers on a telescopic slab structure — each unit you consume is charged at the rate of the slab it falls into, not a single flat rate. So your 50th unit and your 400th unit are priced differently.
What does the marginal rate shown here mean?
₹6.75/unit is what your NEXT unit of consumption costs if you're already in the top slab — this includes the top slab rate, fuel cost adjustment and electricity duty. It's the realistic cost of running one more appliance, like an AC.