Mutual Funds Explained

🟢 A Managed Approach to Investing

Mutual funds are one of the most widely used investment products in Thailand — and one of the most misunderstood. This guide explains what they are, how they work, and how they compare to other investment options.

What a Mutual Fund Is

A mutual fund pools money from many investors and uses that combined capital to invest in a diversified portfolio of assets — such as stocks, bonds, or a combination of both.

When you invest in a mutual fund, you are not selecting individual stocks or bonds yourself. A professional fund manager makes those decisions on behalf of all investors in the fund.

In return for this management, the fund charges an annual fee — deducted from the fund’s assets regardless of performance.

How Mutual Funds Work

Many investors contribute money
           ↓
Fund pools the capital together
           ↓
Fund manager invests across many assets
           ↓
Returns (and losses) shared proportionally
among all investors

Each investor owns units in the fund — not the underlying assets directly. The value of those units rises and falls based on the performance of the fund’s investments.

Types of Mutual Funds

Equity funds — invest primarily in stocks. Higher potential returns with higher volatility. Suitable for longer time horizons.
Bond funds — invest primarily in bonds and fixed income instruments. Generally more stable than equity funds with lower potential returns.
Balanced funds — invest in a mix of stocks and bonds. Aim to provide moderate growth with reduced volatility.
Money market funds — invest in short-term, low-risk instruments. Very stable but low returns. Often used for short-term cash management. Unlike a savings account, fund units are not bank deposits: they are not covered by Thailand’s deposit protection scheme (up to 1 million THB per depositor per financial institution), and you may get back less than you invested.
Index funds — a specific type of mutual fund designed to track a market index rather than actively select investments. Typically lower cost than actively managed funds.

Mutual Funds in Thailand

Thailand has a well-developed mutual fund market regulated by the Securities and Exchange Commission (SEC Thailand).

Thai mutual funds are managed by asset management companies licensed by the SEC. You can buy them through:

Banks, which sell funds on behalf of asset management companies
The asset management companies directly
Securities companies and other SEC-licensed distributors, including online channels

A fund bought at a bank is not a bank deposit. Use the SEC Check First app to verify that a company, product or adviser is licensed.

Two fund types currently offer tax deductions for Thai taxpayers.

RMF (Retirement Mutual Fund): deductible up to 30% of assessable income, capped at 500,000 THB per year together with other retirement savings such as provident funds, GPF and pension insurance. Units must be held for at least 5 years and cannot be sold before age 55.
Thai ESG Fund: deductible up to 30% of assessable income, capped at 300,000 THB per year in a separate limit. Units bought in 2024–2026 must be held for 5 years, and under current rules 2026 is the last year these conditions apply.

The SSF (Super Savings Fund) no longer offers new deductions. 2024 was the last eligible tax year, and existing SSF units must still be held for 10 years.

See our guide: Tax-Optimized Investing.

Mutual Funds vs ETFs

Both mutual funds and ETFs hold collections of assets and provide diversification. The key differences are:

Mutual Funds (Thailand):

Priced once per day after market close
Bought through the asset management company, banks or other licensed distributors
May be actively or passively managed
Low minimums — many funds can be bought from 1 THB (see the fund fact sheet)
Costs: annual fund expenses deducted from the fund, plus possible front-end, back-end or switching fees per transaction (some funds waive them)

ETFs listed on the SET:

Traded during SET trading sessions via a securities account; some are also available through a fund account at end-of-day NAV
Mostly passively managed (index tracking)
Traded in board lots of 100 units; 1–99 units only on the odd-lot board
Costs: annual fund expenses (e.g. 0.40% p.a. for a SET50 ETF) plus broker commission on every trade (commonly 0.15–0.20% for online accounts, lower at some brokers), small exchange and regulatory fees, and 7% VAT on all fees

An ETF is not automatically cheaper. Some Thai index mutual funds charge no front-end or back-end fees and low annual fees. Compare total costs in each fund’s fact sheet.

Tax for individual investors: capital gains from Thai mutual funds and SET-listed ETFs are tax-exempt; dividends are generally subject to 10% withholding tax. ETFs bought on foreign exchanges are treated differently: for Thai tax residents, income earned from 2024 onward is taxable when brought into Thailand.

Neither is universally superior. The right choice depends on individual circumstances, the products available through your chosen platform, and the specific fund in question.

The Role of the Fund Manager

In an actively managed mutual fund, the fund manager makes ongoing decisions about which assets to buy and sell — with the goal of outperforming a benchmark index.

As discussed in the Passive vs Active Investing article, research consistently shows that most actively managed funds do not outperform their benchmark over long periods after fees are accounted for. This does not mean active management has no value — but it means the fee charged should be evaluated carefully against the fund’s actual track record.

Key Takeaways

A mutual fund pools money from many investors to invest in a diversified portfolio
A professional fund manager makes investment decisions on behalf of all investors
Types include equity, bond, balanced, money market, and index funds
Thai mutual funds are regulated by the SEC Thailand and widely available through banks and investment platforms
Mutual funds differ from ETFs primarily in how they are traded, priced, and managed
Fees vary significantly — understanding the total cost of a fund is important before investing

Frequently Asked Questions

Are mutual funds safe?

Mutual funds carry investment risk — their value can fall as well as rise. However, they are regulated products in Thailand and must disclose their holdings, fees, and risk profile. They are significantly safer than unregulated investment schemes.

What is the minimum investment for a Thai mutual fund?

Minimum investment amounts vary by fund and sales channel. Many Thai mutual funds can be bought from as little as 1 THB; the minimum for first and subsequent purchases is stated in each fund’s fact sheet.

How do I choose a mutual fund in Thailand?

Key factors include the fund’s investment objective, its historical performance relative to its benchmark, the total expense ratio, the fund manager’s track record, and whether the fund type matches your goals and time horizon. The SEC Thailand’s fund database at sec.or.th provides standardised information on all registered funds.