Thai tax on foreign income: the remittance rules

If you spend 180 days or more a year in Thailand, money you bring in from the US can now be taxable in Thailand, unless it was earned before 2024 or a treaty says otherwise.

The short version

You're a Thai tax resident if you're in Thailand for 180 days or more in a calendar year [1].
From January 1, 2024, residents pay Thai tax on foreign income they bring into Thailand, even if it's brought in a later year. Before that, income brought in a later year escaped tax [1][2].
Income earned before January 1, 2024 is not taxed when you bring it in, under Departmental Instruction Por. 162/2566 [1][2].
Under the US–Thailand tax treaty, US Social Security is taxable only in the US; other income can get a Thai credit for US tax paid [3][4].
A draft rule to exempt foreign income brought in during the same or the following year has been talked about since 2025, but it isn't law [5][6].

This is general information, not tax advice. Check the Revenue Department at rd.go.th and have a US expat tax preparer (ideally one who also knows Thai tax) check your situation.

What changed on January 1, 2024

Section 41 of Thailand's Revenue Code has always taxed residents on foreign income "brought into" Thailand. For years, the Revenue Department read that to mean only income brought in during the same calendar year it was earned. Leave your 2019 dividends offshore until 2020, and they were never taxed in Thailand.

Two departmental instructions ended that:

Por. 161/2566 (2023) says foreign income brought into Thailand from January 1, 2024 onward is taxable, regardless of the year it was earned [2].
Por. 162/2566 (November 20, 2023) clarifies that this doesn't apply to foreign income earned before January 1, 2024 [2].

The Revenue Department's own explainer for foreigners puts it plainly: foreign income is taxable if it was earned in a tax year starting January 1, 2024 or later, you were in Thailand for 180 days or more that year, and the money was brought into Thailand, whether that year or later [1].

Who it hits

Your situation	Thai tax on money you bring in?
Fewer than 180 days in Thailand this year	No tax on foreign income, even if brought in later [1]
180+ days, money earned before 2024	Not taxed when brought in [1][2]
180+ days, money earned in 2024 or later	Taxable when brought in, any year [1]
180+ days, US Social Security	Taxable only in the US under the treaty [3]
LTR holder (Wealthy Pensioner, Wealthy Global Citizen, Work-from-Thailand)	Exempt under Royal Decree No. 743 [7]

"Brought in" isn't defined only as a wire transfer. The Revenue Department's explainer doesn't spell out how cash withdrawals from a US account or spending on a US card in Thailand are treated, so don't assume a card swipe is invisible; ask a Thai tax adviser how to handle it.

The pre-2024 savings exemption

For most Americans retiring to Bangkok, this is the most valuable rule on the page. Savings you built up before January 1, 2024 can be brought in without Thai tax [1][2]. The challenge is proving it.

Keep a "clean" pre-2024 account. A US account holding only money you had before 2024, with statements to prove it, makes the case simple.
Don't mix new income into it. Once 2024 dividends, Social Security or IRA withdrawals land in the same account, you'll need to show which dollars you sent.
Save year-end 2023 statements for every account, and a record of each transfer to Thailand.
Note what you're sending. Your wire memo and your own spreadsheet won't settle it alone, but they help.

How the US–Thailand treaty helps

The US and Thailand signed an income tax treaty on November 26, 1996 [3]. There is no US–Thailand totalization agreement for Social Security contributions. Three treaty points matter most for Americans:

Social Security (Article 20(2)): benefits paid by one country to a resident of the other are taxable only in the paying country, and this covers US citizens too [3]. So US Social Security you bring into Thailand isn't Thai-taxable.
Private pensions (Article 20(1)): pensions for past employment are taxable only where you live [3]. But the treaty's saving clause lets the US keep taxing its citizens as if the treaty didn't exist, and that article isn't one of the exceptions [3]. In practice, a US citizen living in Thailand can owe tax on pension, 401(k) or IRA money in both countries.
Relief from double tax (Article 25): Thailand gives a credit against Thai tax for US tax paid on US-source income, capped at the Thai tax on that income [3].

Claiming the Thai credit

The Revenue Department's foreign tax credit manual from November 2025 says the credit is only available where Thailand has a tax treaty with the source country, and the US is one of them [4]. Key points [4]:

The credit can't exceed the Thai tax on that slice of income, and unused credit can't be carried forward.
You calculate it separately by country and type of income.
Keep your US return, proof of US tax paid, 1099s and bank records showing the transfer into Thailand.

On the US side, the foreign earned income exclusion doesn't cover pensions, annuities or Social Security [8], so retirees rely on the foreign tax credit (Form 1116) for any Thai tax paid.

Filing a Thai return

If you're resident and taxable, you file P.N.D. 90 or P.N.D. 91, reporting Thai income plus foreign income brought in during the year [1]. The deadline is the end of March for the year before, and you'll need a Thai tax ID.

Thai rates are progressive. The first THB 150,000 of net income is exempt, and rates run from 5% up to 35% above THB 5,000,000 (about USD 4,440 and USD 148,100) [9]. The personal allowance is THB 60,000 (about USD 1,780), and residents 65 or older get up to THB 190,000 (about USD 5,630) of income exempt [9]. Those figures come from a 2021 tax booklet, so check the current Revenue Department figures before you file.

USD conversions use the Federal Reserve H.10 rate of October 30, 2026 (USD 1 = THB 33.76).

The proposed same-year exemption: not law yet

In May 2025 the Revenue Department said it was drafting relief that would exempt foreign income brought in during the year it was earned or the following year, while taxing money brought in later [5]. That would flip the current rules on their head. As of a check of the Royal Gazette register dated October 19, 2026, reported by a Thai law firm, no instrument had been published, and the draft remained a draft [6]. Plan on the current rules until a royal decree or ministerial regulation actually appears.

Don't forget the US side

Your US return comes first, every year: Form 1040 on worldwide income, an FBAR if your foreign accounts total more than USD 10,000 at any time in the year, and Form 8938 if you live abroad and your foreign assets top USD 200,000 at year-end or USD 300,000 at any time if single (USD 400,000 and USD 600,000 if married filing jointly) [10]. Ask in our community group for Americans in Thailand how others are documenting their pre-2024 savings.

Thai tax on foreign income: what changed in 2024 and what it means for Americans