In Sri Lanka, your bill depends first on whether you are billed by CEB or LECO. After that, the biggest factor is your tariff category. A domestic account follows a different logic from a general, industrial, or hotel account. On top of that, some users are billed on a normal single-rate structure while others fall under a time-of-use or solar-related setup.
What usually affects the monthly bill
- The number of units used during the billing period
- Whether the account is domestic, TOU, general, industrial, or another tariff class
- Whether you have rooftop solar under net metering, net accounting, or net plus
- Fixed charges and tax components that apply after the energy charge
How to estimate the bill in a practical way
Start by finding your monthly units in kWh from your previous bill. Then select the correct provider and tariff category. Once you enter the units, the calculator can estimate the block or unit-based charges first, add the fixed charge, and then layer on the tax assumptions used by the site.
Worked example
Assume a domestic household uses 120 kWh in a standard billing cycle. That usage does not get charged at one single rate. Instead, it moves through tariff blocks. Lower blocks are billed at one rate and the next blocks at higher rates. Then the fixed charge is added. After that, taxes are applied to reach the payable total.
This is why two homes with similar usage can still end up with different totals if one stays inside a lower slab while the other crosses into a higher one.
Common mistakes people make
- Using the wrong provider or tariff type
- Comparing a short bill cycle with a full 30-day estimate
- Ignoring fixed charges and taxes
- Assuming solar export value always cancels import cost one-for-one
FAQ
- Is the bill based only on units
- No. Units are the biggest driver, but fixed charges and taxes also matter.
- Why does the bill jump suddenly after a small increase in usage
- Because crossing a slab or entering a higher-priced block can increase the average cost per unit.
- Can I use the same method for CEB and LECO
- The general approach is similar, but the available categories and bill details can differ.
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