Steps to Pay Estimated Tax via Smartphone App (Which I Always Forget) [Explained from e-Tax Payment Information Registration]

Introduction

Hello. I'm Toshio, a 30-something office worker who aims for FIRE (Financial Independence, Retire Early) while working as an IT engineer. Together with my wife and two sons, I am working hard on asset formation every day to expand the options for our whole family.

July 2026, the season for estimated tax payments has arrived again this year.

I forget how to do it every time.

Do I scan the barcode on the payment slip using Rakuten Pay's "Bill Payment"? Or do I go through e-Tax? Even though I did it last year, I completely forgot (lol).

To conclude, when paying national estimated taxes via a smartphone app, you do not scan the paper payment slip with the Rakuten Pay app.

1. Create and submit a "Payment Information Registration Request" on e-Tax

2. Proceed to the "National Tax Smartphone Payment Dedicated Site" from the e-Tax notification

3. Select a compatible app like Rakuten Pay and pay with your balance

This is the flow. I am leaving this as a memo so that my future self won't get lost.

What is Estimated Tax in the first place?

Estimated tax is a system where people whose estimated tax base amount is 150,000 yen or more calculated based on the previous year's income and tax amount determined as of May 15 of that year, pay a portion of their income tax and special reconstruction income tax in advance.
Eligible individuals will be notified of their estimated tax amount by the tax office by June 15 via mail or e-Tax.

In principle, the estimated tax amount is paid in two installments, each being one-third of the estimated tax base amount. It is a system where the amount is settled against the tax amount for that year in the following year's final tax return.

Who is eligible?

• Office workers with side jobs or freelance income (including stock dividends, capital gains, real estate income, etc.)

• Sole proprietors and freelancers

• Roughly speaking, "people who file a tax return every year and have a certain amount of tax due"

Office workers who only have salary income are generally not eligible, but those who file tax returns for side jobs or investments should check. I am exactly in this category.

Payment Schedule

(*Think of it as prepaying 2/3 of the previous year's income tax in two installments)

If you miss the payment deadline, you may be charged delinquent tax. First, check your classification and amount on the notice of estimated tax payment.

Note that if you meet certain conditions, such as expecting a significant decrease in income compared to the previous year, there is a system called an application for reduction of estimated tax. This is a separate matter from the payment procedure here, so please check the National Tax Agency's guidance if necessary.

The first thing to understand: Do not use the barcode on the payment slip

The "smartphone app payment" used here follows a different process than the bill payment seen for local taxes and utility bills.

This is not a procedure for scanning a paper payment slip directly with the Rakuten Pay app.

Since February 1, 2025, access to the National Tax Smartphone Payment dedicated site has been consolidated via e-Tax. For taxes where you have not submitted declaration data, such as estimated tax, you must first create a "payment information registration request" in e-Tax to register the tax item and amount.

In other words, what you need this time is not a paper payment slip, but the following:

• Have e-Tax ready to use

• Details of the estimated tax notice (tax item, target year, period, payment amount)

• A compatible smartphone payment app

• App balance equal to or greater than the payment amount

Even when using Rakuten Pay, the payment source is not a direct withdrawal from a Rakuten Card; according to the National Tax Agency's guidance, it is the app account balance. Please charge the necessary amount in advance.

Steps to register estimated tax payment information in e-Tax

This is the main part that I always forget (lol).

Currently, the old "e-Tax Software (SP version)" has been integrated into the "e-Tax Software (WEB version)," which can be used from smartphones, tablets, and computers. In the official FAQ, the payment information registration request is explained using operation examples for the computer version.

Step 1: Log in to e-Tax Software (WEB version)

e-Tax websiteLog in to the e-Tax Software (WEB version) from "Login" on the.

You can use your usual login method, such as your My Number Card or User Identification Number.

Step 2: Create a new entry from "Perform application/payment procedures"

After logging in, proceed in the following order.

1. Select "Perform Application/Payment Procedures"

2. Select "Create New"

3. Select "Request for Payment Information Registration"

According to the official FAQ, pressing "Perform Application/Payment Procedures" takes you to the "Declaration/Application/Tax Payment" menu, where you then select "Create New".

Step 3: Confirm Submission Destination and Creation Method

Once the submission tax office is displayed, confirm that the details are correct and proceed to the next step.

For the creation method, select "Create a new request for payment information registration".

Step 4: Enter Estimated Tax Details

While checking against your estimated tax notice, enter the following information.

The input format for the taxable period and the wording for the declaration category may change due to the device used or e-Tax updates. Please prioritize confirming that "Reiwa 8 (2026)", "1st or 2nd installment", and "Amount on the notice" match.

If you make a mistake here, you cannot cancel after payment. Double-check the tax item, taxable period, installment period, and amount before submitting.

Step 5: Confirm Details and Submit

Confirm the details in "Confirm/Correct Input Details" and submit from the "Send to Reception System" screen.

After submission, "Confirm Immediate Notification" will be displayed. Proceed to "Confirm Receipt Notification" to open the "Receipt Notification (Payment Classification Number Notification)".

This Payment Classification Number Notification is the gateway to smartphone app payment.

Pay via Smartphone App from the Receipt Notification

Step 6: Select "Smartphone App Payment"

The received notification (Payment Classification Number Notification) displays the available payment methods. Select the smartphone app payment link from among them to proceed to the 'National Tax Smartphone Payment Dedicated Site'.

The payment classification number, tax office, tax type, taxable period, and tax amount are carried over from e-Tax to the dedicated site. There is no need to re-enter your address or name on the dedicated site.

Step 7: Select the app to use on the dedicated site

As of July 29, 2026, the following five apps are supported by the National Tax Agency.

• PayPay

• d-Barai

• au PAY

• Merpay

• Rakuten Pay

Apps that were previously supported may be removed from the list. It is safest to check the latest information on the National Tax Agency 'Smartphone App Payment Procedures' page right before making the payment.

Step 8: Confirm the amount and pay with your balance

Once you select the app to use, you will be redirected to that app. Confirm the payment amount and the balance of your payment source, then finalize the payment.

In the case of Rakuten Pay, you also select Rakuten Pay at this stage. You do not open the Rakuten Pay app first to scan a barcode from 'Bill Payment'.

Once the payment is complete, return to the 'Payment Procedure Complete' screen on the dedicated site to confirm completion. Be careful not to close the browser in the middle of the process.

Step 9: Save the payment record

No receipt is issued for smartphone app payments.

It is a good idea to save the record by selecting 'Download Payment Details' on the completion screen of the dedicated site. You can also check it later via the 'Smartphone App Payment Procedure Completion Notification' sent to your e-Tax message box.

I am the type of person who closes completion screens like this immediately, so I made sure to save it properly this time (lol).

Points to keep in mind before paying

You can only pay amounts of 300,000 yen or less

You can use smartphone app payment if the tax amount is 300,000 yen or less. Some apps may have even lower limits.

The National Tax Agency advises against splitting tax amounts exceeding 300,000 yen into multiple payments for smartphone app settlement. In such cases, consider direct debit or internet banking payment.

No payment fees

There are no payment fees for smartphone app tax payments. However, communication charges are the responsibility of the user.

Points are handled differently by each app

The National Tax Agency advises checking with each payment service provider regarding their point-earning policies. It cannot be stated definitively that "points are always earned because it's tax" or "points are never earned with Rakuten Pay."

It is safer to check the balance charging method and usage limits before worrying about points.

Cannot be canceled once completed

Once the payment procedure is completed on the dedicated site, it cannot be canceled. If you make a mistake regarding the tax item or taxable period, you must contact your local tax office.

That is why checking the details when registering payment information on e-Tax is the most important step.

Beware of double payment with automatic bank transfers

If you use automatic bank transfer for estimated tax, it may be deducted from your account automatically. Since paying via smartphone app could result in a double payment, please check your automatic transfer settings first.

My thoughts after actually trying it

The procedure itself was not difficult.

What is difficult is that you cannot find the entry point even if you search inside Rakuten Pay. The entry point isn't actually in Rakuten Pay, but rather in the "Payment Information Registration Request" on e-Tax.

Once you understand the flow, you just need to remember:

Register on e-Tax → Receive notification → Dedicated site → Rakuten Pay

That's all there is to it.

Even as an IT engineer, I naturally forget administrative procedures that I only use a few times a year (lol). Future me, please open this article before searching for bill payments in Rakuten Pay.

Summary

Here is a summary of the process for paying estimated tax using a smartphone app.

1. Check the tax item, target year, period, and amount on the estimated tax notification.

2. Log in to the e-Tax software (Web version).

3. Proceed to 'Perform application/payment procedures' -> 'Create new' -> 'Request for payment information registration'.

4. Register and submit 'Income Tax and Special Reconstruction Income Tax', the taxable period, the 1st or 2nd installment of estimated tax, and the payment amount.

5. Select smartphone app payment from the received notification (Payment classification number notification).

6. Select a compatible app on the National Tax Smartphone Payment dedicated site and pay using your balance.

7. Save the payment details from the completion screen and also check the completion notification in e-Tax.

This is not the procedure for scanning a payment slip barcode with Rakuten Pay.

This is the part I wanted to save the most this time. I hope this serves as a reference for those who get lost in the same place every time they pay estimated tax.

Official information referenced

• National Tax Agency 'Estimated Tax'

• National Tax Agency 'Procedures for Smartphone App Payment'

• National Tax Agency 'Q&A on Smartphone App Payment'

• e-Tax 'Electronic Tax Payment'

• e-Tax 'How do I create a request for payment information registration?'

Note: This article is intended to provide information based on personal experience and records. Systems and screens are subject to change. For actual procedures, please check the latest official information and your estimated tax notification, and consult with a tax office or tax accountant if tax-related judgment is required.