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Thailand Electricity Bill Calculator
A Thai home electricity bill on the tiered tariff — service charge, Ft and 7% VAT included, at MEA rates for the September 2026 cycle onward.
Bill by units consumed
| Units | Energy charge | Ft charge | VAT | Total (baht) |
|---|---|---|---|---|
| 50 | 150 | 8 | 14 | 210.08 |
| 100 | 300 | 16 | 25 | 379.26 |
| 150 | 450 | 24 | 36 | 548.44 |
| 200 | 600 | 32 | 47 | 717.63 |
| 300 | 1,016 | 49 | 77 | 1,179.94 |
| 400 | 1,432 | 65 | 107 | 1,642.26 |
| 500 | 1,868 | 81 | 139 | 2,125.96 |
| 700 | 2,739 | 114 | 202 | 3,093.37 |
| 1000 | 4,047 | 162 | 297 | 4,544.48 |
Ask about this page
The AI assistant answers only questions about the calculator on this page.
A Thai electricity bill is not units multiplied by a single price, which is what most people assume. It has four parts: a tiered energy charge, a fixed monthly service charge, the Ft charge, and 7% VAT applied on top of all of it. That is why the real cost per unit is always higher than the rate printed in the tariff table.
It also explains something that catches out almost everyone in their first Thai hot season: a modest increase in consumption can produce a startlingly large increase in the bill, because the extra units are charged at a higher tier than the ones before them.
How it works
The energy charge is tiered. Early units cost less than later ones. As consumption crosses a threshold, the units above it are charged at a higher rate. On rate 1.2, units 1 to 200 cost 3 baht each, units 201 to 400 cost 4.1584 baht, and units from 401 upwards cost 4.3583 baht.
The consequence is that going from 200 units a month to 400 does not double your bill — it more than doubles it, because those additional 200 units are charged at a rate nearly 40% higher than the first 200.
The monthly service charge is fixed and applies whether you use a lot of electricity or none at all. Rate 1.1 charges 8.19 baht and rate 1.2 charges 38.22 baht. Even in a month when the property is empty, this part is still billed.
The Ft charge stands for the automatic fuel adjustment. It is the mechanism for passing through changes in fuel costs and purchased power. The Energy Regulatory Commission reviews and re-announces it every four months, and it is multiplied by every unit you use. The current figure is 0.1623 baht per unit.
VAT is charged at 7% on the sum of all three parts above, so it applies to the service charge and the Ft charge as well as to the energy itself.
The 2026 tariff change. The Metropolitan Electricity Authority revised its residential tariff, removing the public lighting cost from customer bills. This took effect from the September 2026 billing cycle. This calculator uses the new rates, so if you are comparing against a bill from before that date the figures will not line up.
One note for anyone renting: many Thai landlords bill electricity at their own flat rate per unit rather than passing on the authority’s bill. That rate is often well above what the authority charges. If your landlord bills you per unit, this calculator tells you what the electricity actually costs, which is a useful thing to know before signing a lease.
Frequently asked questions
Why does my bill rise so sharply in the hot season?
Two reasons compound each other. First, an air conditioner has to work harder to reach the same indoor temperature when it is hotter outside, so it draws more power even with the same setting and the same hours of use. Second, and more significant, is the tiered structure: as total units rise past a threshold, the extra units are charged at a higher rate. The bill therefore grows faster than the consumption does.
What is the difference between rate 1.1 and rate 1.2?
Rate 1.1 applies to homes with a meter of 5 amps or less that use no more than 150 units a month. Rate 1.2 applies to homes with a larger meter, or with a small meter that has exceeded 150 units a month for three consecutive months. An ordinary home with air conditioning is on rate 1.2. Your bill states which one you are on.
How often does the Ft charge change?
The Energy Regulatory Commission reviews and re-announces it every four months: January to April, May to August, and September to December. It reflects changes in fuel and purchased power costs, so it can go up or down.
My landlord charges a different rate. Is that allowed?
It is common for landlords in Thailand to bill electricity at their own flat rate per unit instead of passing on the authority’s bill, and that rate is frequently higher than the real cost. Whether it is permitted depends on your lease and on whether the meter is in your name or the landlord’s. This calculator at least tells you what the electricity genuinely costs, so you can see the size of the mark-up.
My calculation does not match my bill.
Check three things. Does the tariff type you selected match the one printed on your bill? Is your billing cycle before or after September 2026, when the tariff structure changed? And does the Ft charge on your bill match the period this tool uses? Beyond that, a real bill may include other items such as a late payment charge or a balance carried over from the previous month.
Sources
- Metropolitan Electricity Authority (MEA)
- Provincial Electricity Authority (PEA)
- Current Ft charge — PEA
Rates last verified 2 Sep 2026