The Scope of Medical Expense Deductions Is Wider Than You Think
The medical expense deduction allows you to deduct from your income the portion of annual medical expenses exceeding 100,000 yen (or 5% of total income, whichever is lower), up to a maximum of 2,000,000 yen. Eligible expenses go far beyond hospital visits and prescriptions. Transportation costs for medical visits (public transit), the self-pay portion of hospital meals, out-of-pocket dental work (implants, orthodontics), LASIK surgery, and fertility treatment costs all qualify.
A commonly overlooked point is that you can combine the medical expenses of all family members sharing the same household budget. For dual-income couples, having the higher earner file the deduction maximizes the tax benefit. If someone earning 800 man-yen claims a 30 man-yen medical expense deduction, the refund at a 23% income tax rate plus 10% resident tax rate amounts to roughly 66,000 yen. Investing this refund every year yields approximately 83 man-yen over 10 years at 5% compound interest.
Choosing Wisely Between the Standard Deduction and the Self-Medication Tax System
The Self-Medication Tax System, introduced in 2017, allows you to deduct the portion of qualifying OTC drug purchases (switch OTC medicines) exceeding 12,000 yen per year, up to a maximum of 88,000 yen. It is an either-or choice with the standard medical expense deduction - you cannot use both. For people who rarely visit hospitals but frequently buy OTC medicines, the Self-Medication system may be more advantageous.
The decision point is whether total medical expenses exceed 100,000 yen. Books on the Self-Medication Tax System explain that even if medical expenses fall below 100,000 yen, you can still claim a deduction if OTC drug purchases exceed 12,000 yen. Qualifying medicines display a common identification mark on their packaging, so get into the habit of checking at the time of purchase.
Building a System to Reinvest Tax Refunds
Tax refunds from medical expense deductions are deposited into your designated account 1-2 months after filing. By setting up automatic transfers from that account to your brokerage account for mutual fund contributions, you can link tax savings directly to wealth building. Even if the annual refund is just 5 man-yen, compounding at 5% over 20 years turns it into approximately 165 man-yen.
Medical receipts must be kept for 5 years, but filing via e-Tax eliminates the need to attach them. Linking with the MynaPortal system automatically imports medical expense notification data, dramatically reducing manual input. Practical guides on tax returns and refunds are handy references to keep nearby for a smooth filing process each year.
Concrete Steps to Turn Medical Deductions into Wealth
Start by gathering all medical receipts for the current year and calculating the total. If it exceeds 100,000 yen, you qualify for the medical expense deduction. Even if it doesn't, check whether your OTC drug purchases exceed 12,000 yen for the Self-Medication Tax System. Linking e-Tax with MynaPortal automatically imports medical expense data, greatly reducing the filing burden.
Once the refund arrives, channel the entire amount into your NISA account's regular investment plan. Investing a 5 man-yen annual refund at 5% for 20 years yields approximately 165 man-yen. Track your medical expenses in a household budget app or spreadsheet to maintain a running total throughout the year, ensuring you never miss a deduction opportunity. Small tax savings, compounded consistently, create a significant wealth gap over the long term.