Sri Lanka Electricity Bill Calculator (CEB & LECO)
Estimate your monthly CEB or LECO bill from a single number — units consumed. Uses the PUCSL-approved tariff schedule, shows the full block-by-block breakdown, and explains the retroactive-slab effect that catches every Sri Lankan household at least once.
How it works
Sri Lanka's domestic electricity tariff is set by the Public Utilities Commission of Sri Lanka (PUCSL) under the Sri Lanka Electricity Act No. 36 of 2024. Both Ceylon Electricity Board (CEB) and Lanka Electricity Company (LECO) bill the same PUCSL-approved schedule, so the calculator above produces the same number for either utility.
The schedule is block-based with retroactive escalation. That phrase is doing a lot of work and is the single most useful thing this page can teach: your totalmonthly consumption picks a slab, and the slab's rate ladder applies to every unit, not only the units above the previous slab's ceiling. If you cross a slab boundary the entire month re-prices at higher rates — which is why a single extra unit can add hundreds of rupees to the bill.
- Read your meter at the start and end of the billing period; the difference is your units consumed (kWh).
- Look up the slab whose total-units range contains that number. For domestic consumers there are six slabs (A to F).
- Within the slab, multiply the units in each band by the band rate and sum to get the energy charge.
- Add the slab's fixed monthly charge — a flat fee that climbs with the slab and which you pay even at zero units (the minimum bill is the fixed charge).
- If PUCSL has activated a Fuel Adjustment Surcharge (FAS), apply it as a percentage on the energy charge. The FAS has been zero since the PUCSL — Retail Tariff Determination, March 2025.
For 60-day (bi-monthly) cycles common in rural CEB billing zones, the slab boundaries double, not the rates. A household using 120 units over a 60-day cycle is treated as a 60-unit-per-month customer (Slab B), not a Slab D customer. The calculator handles this automatically.
The methodology has an equivalent if/then ladderform that skips the band-table walk — useful as a sanity check. The page's calculateMonthlyDomesticByLadder function in lib/data/sri-lanka-electricity-bill-calculator.ts must always produce the same total to the rupee as the band-table path; both are run against fifteen reference cases at typecheck time.
| Slab | Total units (kWh / month) | Rate ladder | Fixed charge |
|---|---|---|---|
| A | 0–30 | 1–30 @ Rs 6.00 | Rs 150.00 |
| B | 31–60 | 1–30 @ Rs 6.00 · 31–60 @ Rs 8.00 | Rs 400.00 |
| C | 61–90 | 1–60 @ Rs 12.00 · 61–90 @ Rs 28.00 | Rs 600.00 |
| D | 91–120 | 1–60 @ Rs 12.00 · 61–90 @ Rs 28.00 · 91–120 @ Rs 36.00 | Rs 1,000.00 |
| E | 121–180 | 1–60 @ Rs 32.00 · 61–120 @ Rs 40.00 · 121–180 @ Rs 50.00 | Rs 1,500.00 |
| F | > 180 | 1–60 @ Rs 42.00 · 61–120 @ Rs 50.00 · 121–180 @ Rs 60.00 · 181+ @ Rs 75.00 | Rs 2,000.00 |
Worked examples
Frequently asked questions
Sources & references
- PUCSL — Electricity Tariff Schedules (regulator)
- Ceylon Electricity Board — Tariff Information
- Lanka Electricity Company (LECO) — Tariff
- Sri Lanka Electricity Act No. 36 of 2024 (statutory basis)
Calculations follow the PUCSL — Retail Tariff Determination, March 2025 effective from 2025-03-16. Last cross-checked on 2026-05-11. The page will be re-verified each time PUCSL gazettes a tariff revision; revision history lives in the project's git log.
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Comments & feedback
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