Everyone who owns a property in Thailand whether living inside the country or living outside, is legally subject to pay tax on their rental income. If you live inside the country any rental income will go towards your total personal income (salary + rental income) and you will be liable for the personal income tax on the standard sliding scale income tax calculation. If living outside and a non-tax payer in Thailand then the below rules apply.
The process to pay and submit the rental tax is to fill out a PND 91 personal income tax return every year (usually in March) based on income earned for the previous year.
If living outside the country, a withholding tax payment is required to be sent to the government to be paid on your behalf. This can be paid by either the person(s) or company renting your property or you can do it yourself are receiving it. This is applicable to individual rentals or properties in a rental pool/guarantee.
This tax ranges between 10% -15% and is deducted from the tenant on a monthly or yearly basis - depending on how they make the rental payment to you.
Withholding tax is credited back to the landlord if required after they submit their annual income tax liability and is deducted from any payments made there. If you have a Thai company it is easy to claim these payments back when you complete your year-end tax submissions.
If an individual owner/landlord has a TIN (tax identification number) this will also allow them to claim back any WHT payments and ultimately reduce the payment to around 5% down from 15% ensuring their investment and income/earnings are significantly higher.
Please talk to a FazWaz agent for more information on this point to assist with obtaining a TIN.