KRW 300 million at 4% produces only KRW 846,000 a month after tax. To cover KRW 1 million of monthly spending, you need about KRW 54.61 million more principal.
Rates are illustrative, not current product offers or promised future returns. Net means after 15.4% withholding; final tax can change the amount.
On mobile, scroll each table horizontally to compare all rates and gross and net amounts.
| Assumed annual rate | Gross monthly target | Net monthly target (15.4%) |
|---|---|---|
| 2% | 600,000,000 | 709,219,859 |
| 3% | 400,000,000 | 472,813,239 |
| 4% | 300,000,000 | 354,609,930 |
| 5% | 240,000,000 | 283,687,944 |
How much deposit principal generates KRW 1 million a month?
At 4%, the after-tax goal requires about KRW 354.61 million. KRW 300 million covers the gross target, but spending KRW 1 million a month requires enough principal to cover the tax as well.
The table deducts 15.4% for national and local income tax. If a deposit actually qualifies for full tax exemption, use the gross column instead. Check the eligibility rules and limits for the product. NTS withholding guidance
For the interest on money you already have, see monthly interest on KRW 100 million. Both articles cover a Korean resident’s KRW deposit.
What principal supports KRW 500,000, 1 million or 2 million a month?
Interest does not have to cover your entire budget. Compare adding KRW 500,000 a month to other income with funding KRW 2 million of monthly spending entirely from interest.
| Monthly net target | 2% | 3% | 4% | 5% |
|---|---|---|---|---|
| 500,000 | 354,609,930 | 236,406,620 | 177,304,965 | 141,843,972 |
| 1,000,000 | 709,219,859 | 472,813,239 | 354,609,930 | 283,687,944 |
| 2,000,000 | 1,418,439,717 | 945,626,478 | 709,219,859 | 567,375,887 |
A KRW 2 million target changes more than the principal required. Receiving that amount after 15.4% withholding requires about KRW 28.37 million of annual gross interest. This deposit alone exceeds the usual KRW 20 million comprehensive financial-income tax threshold. Further tax may reduce the amount shown. The KRW 1 million target requires about KRW 14.18 million of annual gross interest, so other interest and dividends also matter.
How much more principal do you need if rates fall by 1 percentage point?
Suppose you save about KRW 354.61 million to cover KRW 1 million a month. If the rate falls from 4% to 3% when you renew, the monthly equivalent drops to KRW 750,000. Replacing the missing KRW 250,000 with deposit interest requires about KRW 118.20 million more principal.
At a 2% renewal rate, the same principal produces about KRW 500,000 a month. Keeping the KRW 1 million budget requires twice the original principal. All changes below are measured against the 4% starting point.
| Renewal rate | Principal for 1m/month | Extra principal vs 4% | Monthly net on original principal | Monthly loss vs 4% |
|---|---|---|---|---|
| 4% | 354,609,930 | 0 | 1,000,000 | 0 |
| 3% | 472,813,239 | 118,203,309 | 750,000 | 250,000 |
| 2% | 709,219,859 | 354,609,929 | 500,000 | 500,000 |
Required principal rises by about 33.3% from 4% to 3%, then another 50% from 3% to 2%. A one-percentage-point drop needs more extra savings when the starting rate is lower. Market rates do not immediately change an existing fixed-rate deposit. The spending impact comes when you renew at a lower rate.
Will KRW 1 million actually arrive every month?
KRW 12 million of annual interest does not mean KRW 1 million arrives every month. A monthly-payment deposit pays on its scheduled dates. A maturity-payment deposit pays the interest at maturity.
Actual monthly receipts can vary with product rates, day counts, payment dates and tax truncation. Compare product documents instead of assuming that monthly-payment and maturity-payment deposits offer the same rate. Check early-withdrawal rates and how previously paid interest is settled.
With a maturity-payment deposit, decide where the first year’s spending money will come from. Locking up that money as well may force you to withdraw the deposit before its interest is due.
Is it safe to put the entire amount in one bank?
Since September 1, 2025, eligible deposits are protected up to KRW 100 million per depositor per financial institution, including principal and prescribed interest. Separate accounts or branches at the same institution do not increase the limit. Prescribed interest is the lower of contractual interest and the rate determined by KDIC. KDIC protection limit · FSC FAQ
Putting KRW 354.61 million in one institution leaves the amount above its limit unprotected. You could consider four separate institutions with about KRW 88.65 million each. Check existing balances, room for interest and product eligibility at each institution. Different rates require recalculating total interest.
Practical limits of living on interest
Preserving nominal principal does not preserve purchasing power. If prices rose by an assumed 2% annually, today’s KRW 1 million monthly budget would become about KRW 1.22 million in ten years. This is an illustration, not an inflation forecast. Spending all interest leaves no allowance for rising costs.
Annual interest and dividends subject to aggregation generally require comprehensive financial-income tax review when they exceed KRW 20 million, excluding exempt and separately taxed income. Splitting deposits across banks does not split a person’s taxable income. The table’s 15.4% withholding is not a guaranteed final tax rate. NTS financial-income tax guidance
Reaching the savings target is only part of the plan. Check whether the money can still cover your budget after the next renewal. Compare the offered rate with a rate one percentage point lower.
Check the savings needed for your monthly budget
Use the offered deposit rate to check how much of your monthly budget the interest could cover. The monthly dividend goal calculator also lets you compare the assets needed for a chosen monthly income.
The monthly dividend goal calculator uses gross income. See the input guide below to compare an after-tax target. Dividends do not carry the same payment or principal protection as an eligible deposit.
Change target and yield to calculate principalIn the deposit calculator, change the principal, rate and term to check interest after tax.
Check deposit interest after taxHow to compare an after-tax goal in the monthly dividend calculator
For KRW 1 million a month after 15.4% withholding, enter KRW 1,182,034 gross per month and an annual yield of 4%. This divides the net target of KRW 1,000,000 by 0.846 and rounds up to whole won. Required assets are KRW 354,610,200, which is KRW 270 above the table because the monthly target rounds up.
Use the required-assets result for this comparison. The investment plan’s total-return and reinvestment assumptions are not deposit forecasts. Additional comprehensive tax needs separate assessment.
Frequently asked questions
Does the principal stay intact if I spend KRW 1 million a month?
The principal remains if you spend only the interest and do not withdraw deposit principal. A lower rate at renewal reduces the income from the same savings. Taking the shortfall from principal also reduces later interest.
Can a maturity-payment deposit fund monthly spending?
You need other cash to cover spending before the interest arrives. You can divide interest received at maturity across the following months, but first cover the cash needed before that payment date.
Does splitting deposits across banks reduce tax?
It can help manage deposit-protection limits, but financial income is added up per person. Splitting accounts alone does not reduce income subject to comprehensive tax.
Can I compare deposit interest with monthly dividends?
You can compare the assets needed for a monthly income target. But dividends can be reduced or stopped, and share prices can fall. A smaller calculated asset requirement does not give an investment the same stability as a deposit.
Calculation assumptions and sources
Checked October 9, 2026. Figures use KRW, 12-month simple interest and 15.4% withholding (14% national plus 1.4% local income tax). Rates of 2%, 3%, 4% and 5% are illustrative. Required principal = monthly net target × 12 ÷ [annual rate × (1 − tax rate)], rounded up to whole won. Monthly equivalents divide annual net interest by 12. Interest is spent, so the calculation does not assume compound reinvestment. Local Tax Act
The Bank of Korea’s September 30, 2026 release reports a 3.21% annual rate for newly contracted savings-type bank deposits in August 2026. This aggregate is not an available product quote or a monthly-payment deposit rate. The table’s rates remain illustrative. Bank of Korea source
Product day counts, payment dates, tax truncation and additional comprehensive tax are excluded. Required principal and actual payments can vary with product terms and your tax position.
This article illustrates calculations and is not financial or tax advice. Verify actual rates, payments and your tax treatment against product documents and applicable rules. Disclaimer