How this calculator works
- Pick the tariff category first, then enter only the values that category needs.
- Single-rate and block tariffs use one monthly units field, while TOU and bulk tariffs use peak, day, and off-peak units with maximum demand where required.
- Switch between CEB and LECO category lists. For CEB unit-based tariffs, solar users can also estimate Net Metering, Net Accounting, or Net Plus outcomes with import and export values.
Worked example
For domestic usage of 120 kWh in a 30-day billing cycle, the estimated bill is LKR 3,040.00.
Important assumptions
- Tariffs follow the PUCSL approved table effective from 2025-06-12.
- This version is intentionally simpler than the full CEB and LECO calculators and assumes a standard 30-day billing cycle.
- This breakdown shows subtotal, SSCL at 2.5%, and VAT at 18% applied on subtotal plus SSCL.
- For LECO, the official calculator can also show bill-specific adjustments such as fuel charges. Those additions are not modeled here yet.
- For solar schemes, export-credit rates can vary by agreement and vintage. Net Accounting and Net Plus therefore use a user-entered export credit rate in this version.
FAQ
Are these calculators free?
Yes. lankacalculator tools are free to use and designed to be quick to access without sign-up.
How accurate are the results?
The calculators use clear assumptions and formulas, but results are estimates and should be checked against official documents or provider terms.
Can I use this on mobile?
Yes. The layout is built to work cleanly on phones, tablets, and desktops.
Do you store my inputs?
No account is required for these tools, and calculator inputs are not stored as user profiles in this v1 setup.