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iDeCo Tax Savings Simulator [2026]
Just enter your income, occupation, and monthly contribution to automatically calculate your tax savings and projected payout at age 60.
iDeCo’s 3 Tax Benefits
iDeCo offers tax advantages at 3 stages, making it one of the most powerful tax-saving vehicles available.
| Stage | Tax Benefit | Effect |
|---|---|---|
| Contribution | Full income deduction | Reduces income & resident tax every year |
| Growth phase | Tax-free investment gains | Eliminates the usual 20.315% tax on gains |
| Withdrawal | Retirement income deduction / public pension deduction | Favorable treatment whether taken as lump sum or annuity |
How to Start iDeCo
- Choose a brokerage — Compare fees and fund lineup
- Set your monthly contribution — Limit depends on your occupation (use the simulator above)
- Select investment products — Index funds are recommended for beginners
- Set up auto-deduction — Once configured, contributions run on autopilot
Tax Savings by Income Level
| Annual Income | Contribution (employee) | Annual Tax Savings | 30-Year Total Savings |
|---|---|---|---|
| ¥3,000,000 | ¥23,000/mo | ~¥41,400 | ~¥1,242,000 |
| ¥5,000,000 | ¥23,000/mo | ~¥55,200 | ~¥1,656,000 |
| ¥7,000,000 | ¥23,000/mo | ~¥55,200 | ~¥1,656,000 |
| ¥10,000,000 | ¥23,000/mo | ~¥82,800 | ~¥2,484,000 |
Estimates for single employee with no dependents and no corporate pension.
Frequently Asked Questions
Q. Should I start with iDeCo or NISA first? Generally NISA first. Because iDeCo funds are locked until age 60, it is recommended to secure liquidity with NISA before adding iDeCo contributions.
Q. Why do self-employed people have a higher iDeCo limit? Self-employed individuals are not covered by the corporate pension system, so they have less retirement security. To compensate, their iDeCo contribution ceiling is ¥68,000/month (¥816,000/year).
Q. Can I change my contribution amount later? Yes, once per year. You can also set contributions to ¥0 and continue managing investments as a “non-contributing member.”
Q. Are withdrawals taxed? Lump-sum withdrawals qualify for the retirement income deduction; annuity withdrawals qualify for the public pension deduction. Not the full amount is taxed.
Related Tools
- Savings Goal Calculator — Calculate how long to reach any savings target
- Asset Allocation Simulator — Track your total net worth
- Dividend Growth Simulator — Model dividend income and reinvestment