Many people who have deposited a lump sum into savings accounts ahead of retirement often overlook the fact that interest income affects health insurance premiums, even after hearing about it, without knowing the exact criteria. It is easy to assume that "since the threshold for comprehensive taxation of financial income is 20 million won, you can rest assured as long as your income is below that," but there is a separate threshold for calculating health insurance premiums. This article specifically summarizes the criteria for including deposit interest in health insurance premiums and how it differs from the 20 million won tax threshold.
The tax standard of 20 million won and the health insurance premium standard of 10 million won are different systems.
If financial income, such as interest or dividends, exceeds 20 million won per year, it is combined with other income to recalculate comprehensive income tax; this is called comprehensive taxation of financial income. This 20 million won threshold applies only to taxes.
When calculating health insurance premiums, a completely different standard is used compared to this tax basis. If financial income exceeds 10 million won per year, it is included in the income used for calculating health insurance premiums; if these two figures are mistaken for the same, it is difficult to predict actual premium fluctuations.
A common misconception is applying the 20 million won standard strictly.
Many people think, "If the interest is under 20 million won, there is no problem with taxes or health insurance premiums." However, this is only true when considering tax standards.
The moment interest exceeds 10 million won, it already affects the income used to calculate health insurance premiums. Even if the amount ends up being subject to separate taxation in terms of taxes, it can produce a different result in terms of health insurance premiums.
Therefore, the judgment that “since there is no problem based on taxes, there is no problem with health insurance premiums” is not valid.
If it exceeds 10 million won, the entire amount is recorded, not just the excess.
Under the tax threshold (20 million won), only the amount exceeding the limit—that is, the excess—is combined with other income and recalculated. On the other hand, under the health insurance premium threshold (10 million won), the entire interest is treated as income the moment the threshold is crossed.
This difference can significantly alter the results even with small changes in amount. For example, if we compare two retirees with an annual income of 10 million won from the National Pension alone, the person with 10 million won in interest has their assessed income remain at 10 million won (pension only) because the interest is not reflected in the income used to calculate health insurance premiums.
On the other hand, for a person with 11 million won in interest, the assessed income jumps to 21 million won (the sum of 10 million won in pension and 11 million won in interest) as the entire interest is added beyond the threshold. This means that while the interest increased by only 1 million won, the assessed income increased by 11 million won.
This structure, where the results vary discontinuously depending on whether the baseline is slightly exceeded, is the core characteristic of the health insurance premium standard.
It is not just deposit interest that is subject to aggregation.
Financial income reflected in the calculation of health insurance premiums is not limited solely to bank deposit interest. Dividend income, such as fund distributions or ELS profits, is also included.
Therefore, if you only check the interest deposited in your account, you may miss the total amount. The first step is to verify whether the sum of the deposit interest, fund distributions, and ELS profits received this year exceeds 10 million won.
When converted to the deposit principal, the standard varies depending on the interest rate.
Assuming there is no other income besides pre-tax interest, at an annual interest rate of 3.51 TP3T, the deposit must exceed approximately 286 million won to reach the annual interest of 10 million won. Under the same assumption, at an annual interest rate of 41 TP3T, this standard is reached at approximately 250 million won.
As interest rates rise, the principal required to reach the same interest amount decreases. Therefore, principal standards calculated in the past may no longer be accurate when interest rates change.
This figure is calculated under the assumption that there is only pre-tax interest and no other income, so the result may vary depending on the actual applicable interest rate and the composition of assets held.
Just because you exceeded 10 million won does not mean you will receive a health insurance bill immediately.
While it is true that the full amount of interest is reflected in the income used to calculate health insurance premiums if financial income exceeds 10 million won, it cannot be concluded that this immediately leads to a premium increase notice. This is merely one step in the overall assessment process.
In reality, whether dependent status is maintained or converted to regional subscriber status is determined by considering factors such as pension income and assets like housing. It is difficult to reach a conclusion based on income alone.
Therefore, if you have confirmed that your interest has exceeded the threshold, the next step is to review your total income and asset status together.
What needs to be checked now is the total income and whether the threshold has been met.
The tax threshold of 20 million won and the health insurance premium threshold of 10 million won differ in both the numbers and the method of aggregation. For taxes, only the excess amount is recalculated, but for health insurance premiums, if the threshold is exceeded, the entire amount is considered income.
The first step is to determine where you fall based on a combined total of 10 million won, including deposit interest, fund distributions, and ELS profits. Since accurate eligibility determination and premium calculation vary depending on an individual's income and asset composition, it is best to verify specific figures through the National Health Insurance Service.
Frequently Asked Questions
Q1. If deposit interest exceeds 10 million won, do I have to pay a lot of taxes?
Since the tax threshold is 20 million won, the tax burden does not immediately increase just because the interest exceeds 10 million won. The health insurance premium threshold (10 million won) and the tax threshold (20 million won) are different systems.
Q2. What happens if the interest exceeds 10 million won by even 1 won?
Under the health insurance premium calculation standards, the entire interest, not just the excess amount, is added to income the moment it exceeds 10 million won. Therefore, even slightly exceeding the threshold can significantly increase the assessed income.
Q3. Are profits from funds or ELS included in the calculation of health insurance premiums?
It is included. Financial income used to calculate health insurance premiums includes not only deposit interest but also dividend income such as fund distributions and ELS profits.
Q4. If interest exceeds 10 million won, does the health insurance premium increase immediately?
Reflecting the full amount of interest in income is merely one step in the assessment process. The actual determination of whether to maintain dependent status or switch to regional subscriber status is made by considering pension income, housing, and other asset conditions.
Q5. How much deposit is required to receive 10 million won in interest?
Assuming there is only pre-tax interest and no other income, an annual interest of approximately 10 million won is generated from a deposit of about 286 million won at an annual interest rate of 3.51 TP3T, or about 250 million won at an annual interest rate of 41 TP3T. This figure may vary depending on the interest rate and individual circumstances.