Mortgage schedule + extra payment calculator
See your monthly installment, total interest over the term and a yearly reducing-balance schedule - plus the question banks rarely answer: how many years sooner you finish and how much interest you save by paying this much extra per month. Free to use, no sign-up needed
Your loan
The amount borrowed from the bank, not the home price - after deducting the down payment
The floating rate after the promotion is usually around 5-7%
Money paid above the installment goes straight to principal, which cuts the interest of every remaining installment - try it and see the difference
Results
Enter the loan amount to see the installment and the effect of extra payments
Borrow this much, pay how much a month?
Calculated at an average interest of 6% per year on a reducing balance - the same figures as the calculator above. Enter your own numbers to see the effect of extra payments too.
| Loan amount | 20-year term | 30-year term | 40-year term |
|---|---|---|---|
| ฿1,000,000 | ฿7,164 | ฿5,996 | ฿5,502 |
| ฿1,500,000 | ฿10,746 | ฿8,993 | ฿8,253 |
| ฿2,000,000 | ฿14,329 | ฿11,991 | ฿11,004 |
| ฿2,500,000 | ฿17,911 | ฿14,989 | ฿13,755 |
| ฿3,000,000 | ฿21,493 | ฿17,987 | ฿16,506 |
| ฿4,000,000 | ฿28,657 | ฿23,982 | ฿22,009 |
| ฿5,000,000 | ฿35,822 | ฿29,978 | ฿27,511 |
Mortgage and extra payment FAQ
How much a month for a 2 million baht home loan?
At an average interest of 6% per year over 30 years, the installment is about 11,991 baht a month. Over 20 years it is about 14,329 baht, and over 40 years about 11,004 baht. The longer the term, the lower the installment, but total interest over the term rises a lot because principal is paid down more slowly.
Do extra payments really save interest? How much is worth it?
Yes, and more than most people think. For a 2 million baht loan at 6% over 30 years, paying an extra 3,000 baht a month finishes the loan about 11.6 years sooner and saves about 1,011,058 baht in interest - more than the total extra money paid. The reason is that home loans charge interest on a reducing balance: money paid above the installment goes straight to principal and lowers the interest of every remaining installment. There is no minimum amount that is "worth it" - any extra helps in proportion.
Why do extra payments in the early years work better than at the end?
Because interest is charged on the remaining principal. In the early years principal is still very high, so interest eats almost the whole installment and principal barely falls. Extra payments then cut the principal that is generating the most interest, and the effect compounds through the hundreds of remaining installments. Near the end, principal is small and interest is already low, so the effect is much smaller. See the yearly schedule on this page for how the interest-to-principal split changes each year.
After an extra payment, does the bank cut the installment or shorten the term?
Normally the installment stays the same and the term gets shorter, which saves the most interest and is the method this calculator uses. Some banks let you ask for a lower installment instead, but that saves less interest because the term stays as long. If you want a shorter term, tell the bank clearly that the payment is to reduce principal, not an advance installment payment - the two give very different results.
Is there a penalty for paying early?
Partial extra payments from your own money during normal repayment carry no penalty. A penalty applies when you close the whole account to refinance to another bank within the lock-in period, which is mostly the first 3 years, at about 2-3% of the loan amount. Read the contract conditions carefully, since each bank sets its own.
What is stepped interest and why be careful?
It is interest fixed low for the first 1-3 years and then switching to a floating rate tied to MRR, which is often much higher. Almost all Thai home loans work this way. The caution is that if you calculate the installment at the promotional rate for 30 years, the figure is far lower than reality. Use an average rate over the term of about 5-7%, or turn on stepped-interest mode on this page for a closer picture.
What is MRR, and how does it differ from MLR and MOR?
MRR stands for Minimum Retail Rate, the minimum lending rate a bank charges prime retail customers. Almost all home loans after the promotion period are tied to MRR, e.g. a contract saying the rate is MRR minus 2.50%: if that bank's MRR is 7% a year, the rate you actually pay is 4.50% a year. MLR (Minimum Loan Rate) applies to term business loans and MOR (Minimum Overdraft Rate) to overdraft facilities. All three are set by the bank and move with policy interest rates. The key point is that the MRR in a loan offer is the value on the calculation date only, not a fixed rate for the whole term, so allow for MRR possibly rising when calculating long-term installments.
Why is the installment on a bank website lower than what I actually pay?
Many bank calculators show an installment calculated from the year-1 promotional rate, which is the lowest. In practice most banks set the real installment from the post-promotion rate for the whole term, so it doesn't jump in year 4. Turn on stepped-interest mode on this page, enter the year 1-3 rates and the bank's current MRR, and the system compares the figure that is often advertised with the real installment you should prepare for.
Should I use spare money for extra payments or invest it?
The simplest comparison is whether the interest on your home loan is higher than the return you expect from investing. Paying down a mortgage gives a risk-free, tax-free return equal to the loan's interest rate. If your rate is 6%, extra payments are equivalent to an investment with a guaranteed 6% return, which is hard to find in low-risk assets. But always keep an emergency fund first, because money paid into the loan cannot be taken back.
