National Pension Voluntary Contribution Calculator

Estimate whether additional Korea-related pension contributions improve long-term retirement value.

NPS payback and voluntary contribution analysis

Estimate whether paying back unpaid National Pension months or adding voluntary months improves monthly pension enough to recover the real cost.

Monthly pension increase

₩268,428

Real cost after tax saving

₩1,903,800

Tax saving ₩376,200

Recovery period

0.6 years

After contribution months

120 months

Qualifies for old-age pension

Benefit ratio

37.22x

Verdict

매우 유리

Preserves the Korean NPS payback limits, including 119 maximum payback months, 60 installments, 120-month qualification, and Korean premium-rate assumptions. This English finance calculator calls the same Korean pure calculation module as the Korean page. KRW and Korean statutory thresholds are preserved instead of the old generic percentage stub.

Related calculators

National Pension payback and voluntary contribution guide

This English guide translates the Korean NPS additional-payment page. The calculator calls analyzeAddVoluntary, so the English result follows the same Korean payback, voluntary-contribution, tax-saving, and recovery-period logic.

What payback and voluntary contribution mean

Payback is used when a National Pension subscriber can retroactively pay unpaid or exempted months. The Korean engine preserves the 119 months maximum payback limit, checks the 120 months minimum old-age pension qualification line, and compares pension before and after adding the months.

Voluntary contribution is different. It adds future NPS months when someone is not currently a mandatory workplace or regional subscriber. The Korean model keeps the KRW 1,000,000 minimum income base for voluntary contribution and clamps income to the Korean lower and upper income bases.

Cost, tax saving, and installment interest

The calculator estimates the premium principal from the selected income base and NPS premium rate, then subtracts tax saving using the selected marginal tax rate. Installment payback can use up to 60 installments, and the Korean engine adds installment interest rather than treating every payment as a free lump-sum deferral.

The result reports principal, installment interest, tax saving, real cost, monthly pension increase, recovery years, recovery age, total extra pension, benefit ratio, and net profit. This is why a shallow value-times-rate model cannot be used for this page.

How to read the result

A high benefit ratio is most meaningful when the added months also cross the 120 months qualification threshold. If the user still remains below 120 months after payback or voluntary contribution, the monthly pension increase can look small or the warning message can dominate the recommendation.

The Korean content also compares scenarios by added months and income base. Use those scenario rows to see whether extra months, a higher base, or a different payment method changes the recovery age enough to justify the real cash outflow.