How to Read a Thai Electricity Bill 2026 — line by line, including the TOU bill
The difficulty is not that the tariff is hard to find. It is that even with the rate table open, the lines on the bill do not obviously map onto it — and on a TOU bill there are two energy lines instead of one. This page walks each field, says where its number comes from, and ends with a check you can run against your own meter so you do not have to take this page's word for anything.
Every Thai electricity bill, MEA or PEA, is built from the same four blocks: (1) the account — meter number, contract account, billing month; (2) the meter readings — previous, present, and the difference, which is the units actually consumed; (3) the charges — energy, plus the Ft adjustment, plus the fixed monthly service charge; and (4) 7% VAT applied to the whole of block 3, giving the amount due. The line readers most often cannot find is Ft, which is 0.1623 THB per unit this period and is charged on every unit at the same rate regardless of how much you use. A TOU bill differs structurally in exactly one way: the energy charge is split into two lines, on-peak and off-peak, which are then summed. Everything else is identical. And the single number that best tells you what you actually pay is the total divided by the units — not any figure in the rate table.
What is on the bill — field by field
MEA and PEA do not use identical field names, but the information behind them is the same set. The table follows the order in which it appears on the bill.
| Field | What it means | Where the number comes from |
|---|---|---|
| Meter number / customer number | The identifier of that physical meter, not of the house. It does not follow you when you move. | Assigned by the utility at installation; it is what you quote when you call or file anything. |
| Customer class | Which tariff set applies to this account — 1.1 or 1.2 for a household. It decides which rate ladder is used and how large the service charge is. | Set by the utility from how the premises is used and the monthly volume — not something the customer picks. |
| Billing month / reading date | The span this bill covers. It usually is not the 1st to the end of the month but the gap between two reading dates. | The local reading round, which is why one month can cover 28 days and the next 33 — and the units differ without any change in behaviour. |
| Previous / present reading | The cumulative figures on the meter face at two moments. Neither is the consumption. | Read straight off the meter. You can verify both with your own eyes at your own meter. |
| Units consumed (kWh) | The difference between the two readings — the electricity actually used in the period. | Present minus previous. If it does not match what the bill prints, that is the point at which to call. |
| Energy charge | Electricity priced on your class's rate ladder, before Ft, service charge and tax. On a TOU bill this becomes two lines. | Units multiplied through each tier and summed — not units times one single rate. |
| Ft (fuel adjustment) | The fuel-and-purchased-power adjustment, announced by the ERC for each four-month period. This period it is 0.1623 THB per unit. | Total units times the period's Ft rate — flat on every unit, no ladder. |
| Monthly service charge | A fixed amount per account, independent of consumption: 8.19 THB a month for residential class 1.1 and 24.62 THB for class 1.2. | A constant set by your class. In a very low-usage month this line becomes a large share of the bill. |
| 7% VAT | Tax on the sum of energy, Ft and service charge — not on the energy line alone. | The pre-tax subtotal times 7%. This is why the per-unit price you actually pay is always above the figure in the rate table. |
As real numbers: a household using 300 units in the May–Aug 2026 period gets an energy charge of 150 × 3.2484 = 487.26 plus 150 × 4.2218 = 633.27, i.e. 1,120.53 THB, plus 48.69 THB of Ft, plus a 24.62 THB service charge — a pre-tax subtotal of 1,193.84 THB, plus 83.57 THB of VAT, for 1,277.41 THB due, which is 4.26 THB per unit. To try your own figures, enter your units in the electricity bill calculator; the full formula is at how the bill is calculated.
What is different on a TOU bill — two energy lines
People searching for a TOU bill example are usually thrown by finding two energy lines and not being able to match them to a rate table. In fact the structure is unchanged; exactly one thing moves.
The energy charge splits into two lines. The first is the units consumed on-peak, the second off-peak. Each line has its own unit count and its own rate, and the two sum to the energy charge.
There is no ladder on a TOU meter. The rate depends on when you used power, not on how much. Do not look for a 150-unit or 400-unit step on this bill; there is not one.
Ft, the service charge and VAT are identical. Ft is still 0.1623 THB per unit, charged on all units together without any on/off-peak split; the service charge is still a monthly constant; and 7% VAT still applies to the whole subtotal.
A worked TOU bill: 300 units, 40 % of them off-peak
Line 1, on-peak energy: 180 × 5.7982 = 1,043.68 THB. Line 2, off-peak energy: 120 × 2.6369 = 316.43 THB. Energy charge 1,360.11 THB. Then Ft, service charge and VAT in the same order as before, for 1,533.76 THB due — 5.11 THB per unit, against 1,277.41 THB (4.26 per unit) for the same 300 units on an ordinary meter. This is bill-reading, not advice on whether to switch meters, because the result flips entirely with each household's off-peak share. For that decision see is a TOU meter worth it; for the full rates and hours see the TOU rate schedule 2569.
Check your own bill in three steps
These three work on any bill and need no rate table — only the figures printed on the bill and the face of your meter.
Step 1 — check the units. Present reading minus previous reading must equal the unit count printed on the bill: 7,960 − 7,660 = 300 units. If it does not match, stop and call about that, before looking at anything else.
Step 2 — check against the physical meter. Walk out and read the meter today. It must be greater than or equal to the present reading on the bill. If it is lower, the bill's figure did not come from this meter. How to read each dial type: reading the electricity meter.
Step 3 — find what you actually pay per unit. Divide the amount due by the units. That is your real all-in per-unit price; a 300-unit household lands around 4.26 THB. It will always exceed the rate in the table, because the table excludes Ft, the service charge and VAT. Why the two differ: the per-unit price including tax.
Five lines people most often misread
- The meter reading is not the consumption
- The dial is cumulative since installation. The consumption is only the difference between two readings.
- Ft is not a tax
- It is a fuel-cost adjustment announced by the ERC per period; it moves every four months and has been negative in some periods. History: the Ft timeline.
- The service charge is not per unit
- It is a monthly constant. When a house is empty all month and a bill still arrives, this line plus tax is usually most of it: 8.19 THB on residential 1.1, 24.62 THB on 1.2.
- Billing periods are not equal in length
- The reading round makes one period several days longer than the next, so a jump in units can be a calendar artefact rather than behaviour. Compare per day before concluding anything: checking an abnormal bill.
- The table rate is not the price paid
- The table gives the bare energy rate, before Ft, service charge and VAT. The real per-unit price only comes from dividing the amount due by the units.
What this page cannot tell you about your own bill
This page can tell you what each field means. It cannot tell you where that field sits on your piece of paper, because MEA and PEA lay their bills out differently, and even within one utility the paper bill, the e-bill PDF and the app screen name and order the fields differently. We have deliberately not drawn one specimen bill and called it everybody's, because it would be wrong for half of the readers. What we can give is the field list and its meaning, for you to map onto the document in front of you. Where it genuinely will not map, or a number does not reconcile, ask the issuer: MEA hotline 1130 for Bangkok, Nonthaburi and Samut Prakan, PEA hotline 1129 everywhere else. Have your meter number and billing month ready and the call is much shorter. Not sure which area you are in: MEA versus PEA.
Who wrote this
Frank Lee, Founder of CapSolar — a commercial solar design-and-build company in Thailand with 80+ MWp installed across 150+ projects, 100+ clients served and 85K+ tons of CO₂ avoided. Every project assessment here starts by laying out a building's real bills over several months, both ordinary and TOU, so this page is written from documents we actually read rather than from a rate table alone.
FAQ
Once you can read the bill, the next step is shrinking the energy line
The line you can actually move is the energy charge — Ft, the service charge and tax follow consumption and announcements. If your building's load is mostly daytime, CapSolar will assess for free how much of it a roof could carry.