Updated March 2026 to reflect the publication of Royal Decree No. 805 (2026) in the Royal Gazette, confirming the rooftop solar tax deduction and scheme details.
Thailand’s new tax break for rooftop solar installations offers a rare triple win: lower taxes, smaller electricity bills, and the chance to be part of the country’s push toward a more sustainable future.
If you’re living in Thailand for most of the year, you’re likely considered a Thai tax resident—and that means you’re probably looking for ways to make the most of the available deductions. This incentive, approved by the Thai Cabinet and now enacted through Royal Decree No. 805 (2026), is a practical opportunity to do just that.
Solar Power Tax Incentive Update – March 2026
The solar tax incentive has now been formally enacted through Royal Decree No. 805 (2026) following its publication in the Royal Gazette.
The decree confirms the THB 200,000 personal income tax deduction for qualifying rooftop solar installations and clarifies several practical requirements, including documentation rules and the need for the system to be connected to the electricity grid.
The incentive applies to installations completed between 3 March 2026 and 31 December 2028.
Note:When this article was first published the detailed Royal Decree had not yet been issued. The measure has now been formally enacted through Royal Decree No. 805 (2026). Sign up for our tax alerts to get the latest news direct to your inbox.
What’s on Offer?
The Thai government has approved a generous tax deduction for individuals who install rooftop solar systems on their homes. You can deduct up to THB 200,000 (including VAT) from your gross income, effectively lowering the amount of income that’s taxed.
Here’s what you need to know:
- Who qualifies: Any individual (not a company) who installs a system on their residential property. You must be the same person named on the electricity meter.
- What qualifies: Grid-connected solar systems up to 10 kWp, installed by certified providers, with full documentation and approvals. Only one rooftop solar system per household can be claimed under the scheme.
- When: The deduction will start once the measure is published in the Royal Gazette and will remain in place until December 2028. You claim the deduction in the tax year when the system is installed and connected to the electricity grid.
This isn’t just about reducing your tax bill. A solar system also means smaller energy bills and the potential to sell excess power back to the grid.
Can You Claim It?
Yes—if you’re a tax resident and you file an annual return, you can make use of this deduction. It doesn’t matter what nationality you are, but you do need to own or lease a property where solar can be installed.
If you own a condo, you’ll need to check if rooftop installation is possible and approved. If you lease a home, you may be eligible to claim the deduction if the landlord agrees and the necessary paperwork is completed correctly. Getting the installation registered and grid-connected can involve hurdles, so professional help is often a good idea.
You can also stack this tax break with others, like the THB 100,000 mortgage interest deduction or ESG investment allowances of up to THB 300,000.
What This Means for Expats Living in Thailand
Foreign residents who are Thai tax residents can benefit from this incentive in the same way as Thai nationals.
To qualify, you must:
- Spend 180 days or more in Thailand in a calendar year
- File an annual Thai personal income tax return
- Install the system on a property where you are the registered electricity user
For expats, the most common situations include:
- Retirees installing solar on their home in Thailand
- Long-term residents reducing electricity costs on private villas
- Foreign residents installing solar on leased property with landlord approval
However, there are practical considerations. Foreigners cannot own land in Thailand, so installations are usually carried out on leased property or condominium buildings, and approval from the property owner or building management may be required.
If the installation is paid for using funds transferred from overseas, it is also worth ensuring that any remitted income is treated correctly for Thai tax purposes.
How Much Can You Save?
Let’s say you spend THB 150,000 installing a 5 kWp rooftop solar system. If you’re in the 20% tax bracket, that means a potential tax saving of THB 30,000. Spend the full THB 200,000 and you could save up to THB 40,000, depending on your income.
And that’s just the tax saving. Add in lower monthly electricity bills and potential income from selling excess power, and the financial benefits are even more compelling.
Selling Excess Power Back to the Grid
Households can sell surplus power back to the Metropolitan Electricity Authority or Provincial Electricity Authority under the government’s net billing scheme. The buy-back rate is 2.20 baht per kilowatt hour compared with an average retail price of about 4 baht. Systems up to 10 kW qualify and agreements may run for up to ten years. A full net metering scheme, which would credit solar generation at the full retail rate, is still under consideration.
A Real Example
You are retired and living in Chiang Mai. You install a THB 150,000 solar system on your home. You claim the full amount as a deduction on your 2025 or later return, saving THB 30,000 in tax. Over time you cut your electricity bill in half and may even earn a small return from feeding energy back to the grid.
It’s a smart investment—and a simple way to align your finances with your values.
What to Watch
Like any tax incentive, there are a few things to be careful about:
- Getting approval: The system must be grid-connected and properly registered.
- Documents matter: You’ll need complete, accurate invoices and installation approvals.
- Property rules: Foreigners can’t own land, but you can own condos or lease homes. You may need to obtain landlord cooperation and find a workaround for grid registration.
- Audit risk: If you remit foreign funds to pay for the system, make sure they’re declared correctly.
- Installer requirements: The installation must be carried out by a VAT-registered supplier who issues an official e-tax invoice, which must be retained for tax purposes.
If you are interested in this tax incentive, we can help ensure everything is filed correctly.
Should You Consider Installing Solar in Thailand?
With electricity prices rising and the Thai government offering tax incentives, rooftop solar is becoming increasingly attractive for homeowners. For many residents, the combination of tax savings, lower electricity bills and long-term energy security makes solar a compelling investment.
Final Thoughts
This tax incentive offers a simple way to cut your tax bill, lower your electricity costs and support a greener Thailand. With the scheme now running until December 2028, this is a good time to explore whether rooftop solar is suitable for your home.
By going solar, you’re not just saving money, you’re making your property more competitive in an evolving market and contributing to Thailand’s transition toward a greener future.
To keep up with the latest news on Thai tax and how it affects you, sign up for our tax alerts, and if you have any questions on this or other tax matters, book a free call to speak with our team.
