How to use e-Tax
Account setup, My Number authentication, filing, submission records, and common errors.
e-Tax is the free national electronic-filing system: authenticate with a My Number card (the standard route for new users since October 2025), prepare the return in the Return Preparation Corner, transmit it, and save the acceptance notice — payment is arranged separately.
Effective: 2026-01-01 to 2026-12-31
Professional review pending — treat as draft and confirm with the authorities.
Key points
- e-Tax is free and prepares plus transmits national returns.
- A My Number card is the standard authentication for new users since October 2025.
- Mynaportal can prefill supported salary, pension, medical, donation, insurance, and mortgage data.
- Save the acceptance notice; filing is separate from payment.
Setup and authentication
Create an e-Tax account and authenticate. Because the NTA stopped issuing new ID-password credentials on October 1, 2025, new users authenticate with a My Number card via a smartphone or card reader. The card proves your identity so the return can be transmitted without paper. Existing ID-password users can continue under the transitional rules.
Filing and records
Prepare the return in the Return Preparation Corner, using Mynaportal to import supported certificates where available, then transmit. Keep the acceptance notice (受信通知) as proof of filing. Common snags are card-reader/app issues, an expired certificate, and confusing filing with payment — you still choose a payment method afterward.
Who this is for
- Anyone filing electronically
- Employees and simple sole proprietors
What this is not
- Full bookkeeping (e-Tax is not a ledger)
- My Number card certificates expire and need renewal; check validity before filing season.
Frequently asked questions
Do I need to file a tax return in Japan?
Many employees do not, because tax is settled by year-end adjustment (年末調整). You generally must file (確定申告) if you have side income over ¥200,000, two or more employers, self-employment income, sizeable investment or crypto gains, or you want to claim deductions like large medical costs or a first-year mortgage credit. Filing season is Feb 16 – Mar 15 via e-Tax. When unsure, check the NTA guidance or ask a 税理士.