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Tariff Classes Explained

Government Office Electricity in Thailand — and which tariff class state bodies actually sit in

People search “ค่าไฟหลวง” expecting a special government rate. Per the current MEA and PEA rate tables there is none — state offices are billed on the ordinary business classes and then split into small/medium/large by kilowatts. This page shows which class applies, what it costs per unit, and why the “Class 5” so many sites cite is not the government class at all.

8 min readLast updated: 8 Sep 2026Data as of: Sep–Dec 2026

There is no separate “government” electricity tariff. Both MEA's and PEA's rate tables place state offices, any other government body, local administrative organisations and state enterprises inside the ordinary business classes — Class 2 (small) / Class 3 (medium) / Class 4 (large) — split purely by highest 15-minute average demand. An ordinary government office below 30 kW therefore sits in Class 2 and pays the ladder 3.2484 / 4.2218 / 4.4217 THB per unit plus a 33.29 THB monthly service charge, then Ft 0.1623 THB/unit and 7% VAT — about 4.77 THB per unit all-in at 1,500 units a month. (Full tariff structure explains the rest.)

How much per unit does a Thai government office pay for electricity?

An ordinary low-voltage government office drawing less than 30 kW sits in Class 2, small general service. Energy is charged on a ladder — 3.2484 THB/unit for the first 150 units, 4.2218 for units 151–400 and 4.4217 from unit 401 — plus a 33.29 THB monthly service charge, all before Ft and VAT.

Actual monthly bill (Class 2 low voltage, Ft 0.1623 and 7% VAT included)

Units / monthEnergy (THB)Total bill (THB)Effective THB/unit
3001,120.531,286.694.29
5001,984.882,246.274.49
1,0004,195.734,698.714.70
1,5006,406.587,151.154.77
3,00013,039.1314,508.474.84

Every figure is computed at render from the ladder + the 33.29 THB service charge + Ft 0.1623 THB/unit (period Sep–Dec 2026) + 7% VAT — nothing is typed in. When the ERC announces a new Ft period the table moves with it. What Ft is and how it is calculated.

If the site takes supply at 12–24 kV (MEA) / 22–33 kV (PEA), Class 2 is not a ladder at all but a single rate of 3.9086 THB/unit with a 312.24 THB monthly service charge — cheaper per unit, but nearly ten times the fixed charge.

How does a government electricity bill differ from a household one?

The difference is structural, not a discount. Households sit in Class 1: a pure consumption ladder, a service charge of only 8.19–24.62 THB/month, and no demand charge at all. Government bodies are on business rates, and from Class 3 upward the bill adds a demand charge in THB per kilowatt, a 312.24 THB monthly service charge, a power-factor penalty and a minimum-charge floor.

What a government bill has that a household bill does not

Demand charge — Class 3 at low voltage bills 221.50 THB per kilowatt of the month's highest 15-minute average demand, separately from the energy rate (3.1751 THB/unit). One short simultaneous start-up of the chillers can therefore lift the whole month's bill.

Power factor and the minimum-charge floor

If the highest 15-minute reactive demand exceeds 61.97% of active demand, the excess is billed at 56.07 THB per kVAr, and the month's charge may not fall below 70% of the highest demand charge in the trailing 12 months. A government building closed for a long recess, or one that has moved out, therefore still owes a floor amount.

Another common mix-up: the free-50-units measure does not apply to organisations. The official condition states the beneficiary must not be a juristic person and must hold state-welfare eligibility — it is a household measure, not a public-sector discount. (Who qualifies for 50 free units.)

Government offices, temples, schools, foundations — which class is each?

Class 5 “specific business” means hotels and residential-rental businesses — not government. Both MEA's and PEA's definitions say so verbatim. State offices fall under Class 2/3/4 by kilowatts; temples and places of religious observance sit in Class 1, residential; and Class 6, non-profit organisations, expressly “does not include” state bodies.

Who sits in which class (per the utilities' own class definitions)

UserClassDeciding test
Government offices · any other state body · local administrations · state enterprises · embassies · international organisations2 / 3 / 4Under 30 kW = Class 2 · from 30 kW up to under 1,000 kW with a 3-month average of 250,000 units/month or less = Class 3 · 1,000 kW or more, or over 250,000 units/month = Class 4
Temples · monastic residences · places of worship of every religion1 — residentialNamed directly in the Class 1 definition; no kilowatt test
Organisations providing services without remuneration (foundations, charities)6 — non-profitThe definition expressly excludes state bodies, state enterprises, local administrations and foreign entities
Hotels · residential-rental businesses (30 kW and above)5 — specific businessThis is what Class 5 actually is — the word “government” appears nowhere in it
Agricultural water pumps of government agencies · farming cooperatives7 — agricultural pumpingThe one place “government agency” appears outside Classes 2/3/4
“Schools” has no single answer. A state school is a government office and lands in Class 2/3/4 by kilowatts; a private or foundation-run school depends on whether it meets Class 6's “provides services without remuneration” test — and the utility decides that from how the premises are used, the customer does not choose. When in doubt call MEA 1130 / PEA 1129. (How many customer classes there are and where to check yours.)

What does a non-profit organisation (Class 6) pay per unit?

Class 6 at low voltage charges 2.8013 THB/unit for the first 10 units and 3.8919 from unit 11, with a service charge of just 20.00 THB/month. At 12–24 kV it is a flat 3.5849 THB/unit, and at 69 kV and above 3.4149 THB/unit, with a 312.24 THB monthly service charge.
Class 6 also has an optional TOU rate (6.2), which brings a demand charge with it; once chosen, the customer must stay on it at least 12 months before asking to return to 6.1 — the same mechanics as the TOU rate schedule for other classes.
A Class 3 body on TOU (3.2, low voltage) pays 4.3297 on-peak / 2.6369 off-peak THB per unit plus a 210.00 THB/kW demand charge. A Monday-to-Friday daytime government office sits almost entirely inside the on-peak window, which is exactly why TOU rarely helps office buildings.

How to check which class your organisation is on

Four steps, using paperwork you already have — no guessing.

  1. 1. Open the bill for that specific premises

    The class attaches to the premises and that meter, not to the organisation as a whole — one agency with several buildings can legitimately sit in different classes. (Which number on the bill and on the meter is which.)

  2. 2. Read the month's peak demand

    If the bill carries a demand line in THB per kilowatt, the site is already Class 3 or above; if there is none and energy is billed on a pure ladder, it is Class 2. Fractions of a kilowatt are rounded at the half: below 0.5 kW is dropped, 0.5 kW and above counts as 1 kW.

  3. 3. Compare against the 30 kW and 1,000 kW lines

    The move is not symmetric: in any month peak demand reaches 30 kW, a Class 2 site is reclassified to Class 3/4/5 as applicable — but to go back down it must stay under 30 kW for 12 consecutive months, and still be under in the month after that.

  4. 4. If it does not match, ask the utility to review it

    The class is assigned by the utility from how the premises are used — it is not a customer choice. If the classification does not match actual use, contact MEA 1130 (Bangkok, Nonthaburi, Samut Prakan) or PEA 1129 (elsewhere) with the reference numbers from the bill.

What this page does not cover

This page answers the organisational side only. For your own household bill see how much electricity costs in Thailand; for the whole rate structure in one place see the Thai electricity tariff; and for an agency's construction-site supply that is Class 8 temporary power, priced on an entirely different basis.

Who wrote this page, and against what

Frank Lee, Founder of CapSolar — a Thai commercial & industrial solar EPC with 80+ MWp installed across 150+ projects for 100+ clients, and over 85,000+ tons of CO₂ avoided. Every rate on this page was read from the tariff tables MEA and PEA publish themselves and cross-checked line by line between the two. Figures the utilities do not publish are not guessed here.

FAQ

The rate tables contain no discount for being a state body: both sides pay the same base tariff, the same Ft period and the same 7% VAT. What differs is structure — households pay a pure ladder with a 8.19–24.62 THB service charge, while a Class 3/4 organisation also carries a demand charge and a minimum-charge floor. Effective cost per unit can therefore land above or below a household's, depending on how steady the load is.

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