RMF stands for Retirement Mutual Fund. This special fund allows tax benefits for investors. By investing in the RMF
you can exempt large amounts of your personal income tax by up to 15% in a single year as long as the total amount

you invest in provident funds or Government Pension Funds does not exceed 300,000 Baht in the same year. The main condition attached is that the units can only be redeemed after a five year period and when the unit-holder reaches 55. 

 

LTF stands for Long Term Equity Fund. It was designed to help promote long-term savings and it is another new
investment tool for creating tax privileges. Investment in LTF is an additional tax exemption set apart from RMF and provident funds. LTF's investors will receive an income tax concession on the amount of their contribution to the fund. 

The contribution may not exceed 15% of total annual income, with a maximum of 300,000 baht each year. Capital gains from the redemption of the units will also be exempt from tax. Simply hold the investment units for at least five consecutive years (If investors put money in the LTF by the end of the first year, the units can be sold back to the LTF in the fifth year of holding. That means the real holding period is just three years plus a few more days). 

FYI, Foreigners who live in Thailand for more than 180 days in any calendar year and earn income here are eligible for using the allowances given in the following example in calculation of their personal income tax. You can ask more information how to invest in RMF & LTF from almost every bank and financial institution, I believe they will all be willing to help to you.