Thailand’s Revenue Department has set out the rules for exempting individuals from personal income tax on money spent buying and installing rooftop solar power systems, capped at THB 200,000.
Thailand’s Revenue Department has issued Notification of the Director-General of the Revenue Department on Income Tax (No. 470), setting the rules, procedures and conditions for the exemption. It was announced on 30 September 2026 by Director-General Somsak Ananthawat and takes effect from 3 March 2026.
The exemption is provided under Royal Decree No. 805 B.E. 2569 (2026), issued under the Revenue Code. It covers income actually paid for equipment and installation of a solar power generation system on a roof, rooftop or any other part of a building that people may occupy or use. Examples include the roof of a home, a carport or a storage shed within the residential premises.
Who qualifies
The income earner must be liable for personal income tax. Ordinary partnerships, unincorporated bodies of persons and undivided estates are excluded. The claimant must be a Category 1 (residential) electricity user and be registered as the user under the laws governing the Metropolitan Electricity Authority or the Provincial Electricity Authority. The claimant must also be the person who applied to connect to that authority’s grid. Total installed capacity for the home must not exceed 10 kilowatts.
Timing and limits
The contract, purchase order, work order or similar agreement, and the grid connection application must be made between 3 March 2026 and 31 December 2028. The exemption is claimed in the tax year in which the grid connection is completed. Each income earner may pay for no more than one system and may claim the exemption only once during that period.
Spouses
Where only one spouse has income, that spouse may claim up to THB 200,000. Where both have income and each files separately on assessable income under Section 40(1), each may claim up to THB 200,000. Where spouses file jointly under Section 57 sexies, the income earner may claim up to THB 200,000, and the spouse’s portion is also entitled to an exemption of up to THB 200,000.
Evidence required
Claimants need three documents:
- an electronic tax invoice from a VAT-registered seller or service provider named by the Director-General under Clause 12 of Ministerial Regulation No. 384 (B.E. 2565 / 2022), showing the buyer’s taxpayer identification number
- the grid connection application naming the claimant
- the document granting permission to connect, also naming the claimant
The invoice must carry wording such as “Solar Rooftop”, “solar cell panels” or “solar energy generation panels”. This requirement applies to invoices issued from the date of the notification. All three documents must name the same person.
The claimant must notify the relevant electricity authority of the intention to claim. The authority must then send the data electronically to the Revenue Department’s Information Technology Division by 15 January of the following year, unless the Director-General prescribes otherwise.
Other conditions
A VAT-registered claimant who has deducted the VAT on the invoice from output tax under Section 82/3 cannot use the same invoice for the income tax exemption. The exempted amount is deducted from assessable income under Section 40, after expenses under Sections 42 bis to 46.
Anyone who claims the exemption without meeting the conditions loses the right to it and must add the amount to income when calculating personal income tax. Those who file an additional return for that tax year also face a surcharge under Section 27 of the Revenue Code.
