submit

Submission Preparation Checklist (Submission Preparation)

A skill for performing the final check of tax return documents and providing guidance on submission methods. Use this as the final step after the preparation of the tax return is complete.

Loading settings (execute first)

1. shinkoku.config.yaml Read with the Read tool
2. If the file does not exist, /setup guide the user to run the skill and exit
3. Understand the setting values, and convert relative paths to absolute paths based on CWD:
   • db_path: CLI script --db-path used for arguments
   • output_dir: Base directory for outputs such as progress files
   • Each directory: used when referencing files

Loading progress information

After loading the settings, load the handover file and understand the results of the previous step.

1. .shinkoku/progress/progress-summary.md Read with the Read tool (if it exists)
2. Read the following handover documents with the Read tool (if they exist):
   • .shinkoku/progress/07-income-tax.md
   • .shinkoku/progress/08-consumption-tax.md
   • .shinkoku/progress/02-assess.md
3. Use the loaded information in subsequent steps (avoid asking the user again)
4. If the file does not exist, skip it and confirm the necessary information directly with the user

Basic policy

• Systematically check the final checklist before submission
• Present a comparison and recommendation of submission methods (e-Tax / mail / bringing to the tax office)
• Specifically point out common mistakes and omissions and encourage corrections
• Also provide guidance on what to do after submission

Step 0: Verification of taxpayer profile

profile.py Obtain taxpayer information from config and verify that there are no omissions.

shinkoku profile --config shinkoku.config.yaml

Verification items

□ 氏名（姓・名）が登録されているか
□ 住所（郵便番号・都道府県・市区町村・番地）が登録されているか
□ マイナンバーが登録されているか（has_my_number: true）
□ 所轄税務署名が登録されているか
□ 提出方法（e-tax/mail/in-person）が設定されているか

If there is missing information, guide the user to fill it in (/setup rerun the skill or manually edit config).

Step 0.5: Confirmation of supported scope

Check the support level of shinkoku, and if there is income corresponding to Partial/Out, alert the user. For details on the support status, refer to the /capabilities skill.

• Partial: Income calculation is completed by shinkoku, but some forms (such as Form 3) require manual creation or entry in the tax return preparation corner
• Out: If there is applicable income, guide the user to consult a tax accountant

Step 1: Final confirmation of the tax return data

Perform checks for each of the following categories. For detailed check items, refer to references/submission-checklist.md .

Check category

1. Income tax return: Calculation results for Form 1 (income, deductions, tax amount) and Form 2 (breakdown, details)
2. Blue return financial statements: Consistency of the profit and loss statement and balance sheet (only for those applicable)
3. Consumption tax return: Verification of taxable sales and tax payable (only for those applicable)
4. Form 4 (loss return): Verification of the content stated for carryforward losses (only for those applicable)
5. Depreciation schedule: Verification of fixed asset depreciation calculation (only for applicable persons)
6. Attached documents: Withholding tax slip, deduction certificate, specified account report, etc.

Step 2: Final check for common mistakes

Before submitting, check for the following typical mistakes. Also refer to reference/common-mistakes.md.

Fatal mistakes (may invalidate the filing)

1. Missing My Number entry: Is My Number entered on Form 1 and Form 2?
2. Missing signature/seal: For paper submission, is there a signature? (As of the 2021 tax year onward, a seal is not required)
3. Insufficient attached documents: Are all required documents for the first year of the housing loan deduction attached?

Amount errors (cause of additional assessment/insufficient refund)

1. Pitfalls of furusato nozei + final tax return: Donations made using the one-stop special exception must also all be listed on the tax return if you file a final tax return (the one-stop exception becomes invalid)
2. Failure to deduct insurance proceeds for the medical expense deduction: Are amounts compensated by insurance, etc., deducted?
3. Failure to meet requirements for the blue return special deduction: If not filed via e-Tax, the deduction drops from 650,000 yen to 100,000 yen
4. Housing loan deduction and withholding tax amount: If the deduction amount exceeds the withholding tax amount, the excess is deducted from inhabitant tax (subject to a cap)
5. Calculation error in the employment income deduction: For the 2025 tax year, the minimum guaranteed amount is raised to 650,000 yen

Procedural mistakes

1. Misunderstanding the submission deadline: Income tax is March 15, consumption tax is March 31
2. Deadline for refund claims: Can be submitted within 5 years from January 1 of the following year (no March 15 restriction)
3. Late submission of blue return: If submitted on or after March 16, the 650,000 yen deduction becomes 100,000 yen

Step 3: Choosing the submission method

Compare and explain the 3 submission methods:

Method 1: e-Tax (electronic filing) [Recommended] — Substitute input with Claude in Chrome

メリット:
  - 24時間提出可能（提出期間中）
  - 添付書類の提出省略が可能（5年間保存義務あり）
  - 青色申告特別控除65万円の要件を満たせる
  - 還付金の処理が早い（通常3週間程度、書面は1〜2か月）
  - 自宅から完結

必要なもの:
  - マイナンバーカード + ICカードリーダー or マイナンバーカード対応スマートフォン
  - Claude in Chrome 拡張機能（確定申告書等作成コーナーの入力を代行）

手順:
  1. Chrome で確定申告書等作成コーナーにアクセス
     （https://www.keisan.nta.go.jp/）
  2. Claude in Chrome の /e-tax スキルで入力を代行
     - shinkoku の税計算結果を基に各画面のフォームに自動入力
     - 画面遷移・入力値はユーザーが目視確認
  3. マイナンバーカードでログイン・電子署名（手動操作）
  4. 送信前に内容を最終確認
  5. 電子署名を付与して送信
  6. 受付番号を控える（送信後に表示）
  7. 受信通知を確認（メッセージボックスに届く）

Method 2: Mail

メリット:
  - 税務署に行く必要がない
  - 通信日付印が提出日になる（期限日の消印有効）

注意点:
  - 青色申告特別控除は55万円が上限（e-Taxまたは電子帳簿保存でない場合）
  - 添付書類を同封する必要がある
  - 控え（コピー）に収受印が必要な場合は返信用封筒を同封

手順:
  1. 申告書を印刷（A4白黒で可）
  2. 添付書類を台紙に貼付
  3. 確定申告書の控え（コピー）を作成
  4. 以下を封筒に同封:
     - 確定申告書（原本）
     - 添付書類（各種証明書等）
     - マイナンバーカードの写し（表裏）
     - 控えが必要な場合: 確定申告書の控え + 返信用封筒（切手貼付）
  5. 所轄税務署宛に郵送（「確定申告書在中」と記載）
  6. 簡易書留または特定記録郵便を推奨（発送の証拠を残すため）

宛先の確認:
  国税庁「税務署の所在地などを知りたい方」で所轄税務署を検索

Method 3: Bring to the tax office counter

メリット:
  - その場で受付印をもらえる
  - 不備があればその場で指摘される

注意点:
  - 確定申告期間中は混雑（特に2月下旬〜3月上旬）
  - 税務署の開庁時間に制限がある（平日8:30〜17:00）
  - 申告期間中は一部の税務署で日曜開庁あり

手順:
  1. 申告書を印刷
  2. 添付書類を準備
  3. 控え（コピー）を持参
  4. 所轄税務署の窓口に提出
  5. 控えに受付印をもらう

Summary comparison of submission methods

Item	e-Tax	Mail	Bring in person
Blue 650,000 yen deduction	Yes	No (550,000 yen)	No (550,000 yen)
Omission of attached documents	Yes	No	No
Refund processing	Fast (about 3 weeks)	Slow (1–2 months)	Slow (1–2 months)
Available submission hours	24 hours	Can be sent anytime	Only during office hours
Receipt confirmation	Immediate (receipt notification)	Wait for copy to be returned	Receipt stamp on the spot

Step 4: Confirming the filing deadline

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
令和7年分（2025年）確定申告の提出期限
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

■ 所得税の確定申告
  提出期限: 令和8年（2026年）3月16日（月）
  ※ 3月15日が日曜日の場合は翌月曜日
  ※ 還付申告は令和8年1月1日から提出可能

■ 消費税の確定申告
  提出期限: 令和8年（2026年）3月31日（火）

■ 納付期限
  所得税: 申告期限と同日（3月16日）
  消費税: 申告期限と同日（3月31日）
  ※ 振替納税の場合は4月下旬に口座引落し

■ 青色申告特別控除65万円の期限
  期限内申告（3月16日まで）が必須要件
  ※ 1日でも遅れると65万円 → 10万円に減額
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Step 5: Guidance on payment methods

If the declared tax amount is a payment (positive):

Method	Fee	Notes
Direct payment (e-Tax)	Free	Prior notification required
Direct debit	Free	Prior notification required, account debit
Credit card	Payment fee applies	National Tax Credit Card Payment Site
Convenience store payment via QR code	Free	300,000 yen or less
Financial institution / tax office counter	Free	Payment slip required
Smartphone app payment	Free	Supports Pay payments

Step 6: Post-submission to-do list

□ 申告書の控えを保管する（e-Taxの場合は送信データを保存）
□ 受付番号・受信通知を記録する
□ 添付省略した書類を5年間保存する
□ 帳簿書類を7年間保存する（青色申告の場合）
□ 納付がある場合は期限内に納付する
□ 還付がある場合は振込を確認する（3週間〜2か月）
□ 住宅ローン控除2年目以降は年末調整で対応可能
  （税務署から届く「住宅借入金等特別控除申告書」を勤務先に提出）
□ 消費税の届出書の提出が必要な場合は対応する
  （簡易課税選届出、課税期間の短縮など）

Outputting the handover document

After presenting the summary, output the following file with the Write tool. This allows the results to be carried over to the next step even if the session is interrupted or a Compact occurs.

Outputting step-specific files

.shinkoku/progress/09-submit.md Output in the following format to:

---
step: 9
skill: submit
status: completed
completed_at: "{当日日付 YYYY-MM-DD}"
fiscal_year: {tax_year}
---

# 提出準備・チェックリストの結果

## 提出方法

- 選択した提出方法: {e-Tax/郵送/窓口}

## チェックリストの完了状態

- 所得税の確定申告書チェック: {完了/未完了}
- 青色申告決算書チェック: {完了/未完了/該当なし}
- 消費税申告書チェック: {完了/未完了/該当なし}
- 添付書類チェック: {完了/未完了}

## 提出期限

- 所得税: 令和{年}年{月}{日}日
- 消費税: 令和{年}年3月31日（該当者のみ）

## 納付方法・金額

- 所得税の納付額: {金額}円（{納付方法}）
- 消費税の納付額: {金額}円（{納付方法}）（該当者のみ）

## 次のステップ

提出後のやることリストを確認する

Updating the progress summary

.shinkoku/progress/progress-summary.md Update (create new if it does not exist):

• YAML frontmatter: fiscal_year, last_updated (current date), current_step: submit
• Table: Update the status of all steps (set submit to completed)
• State that all steps are complete

Guidance after output

After outputting the file, tell the user the following:

• "The handover document has been saved to .shinkoku/progress/ . Even if the session is interrupted, the results can be carried over to the next skill."
• Inform that all steps of the income tax return have been completed

Additional Resources

Reference Files

For detailed check items, refer to the following:

• references/submission-checklist.md — All check items for Form 1, Form 2, financial statements, consumption tax, and attached documents (separate taxation is not covered)

Disclaimer

• This information is based on the income tax return for the Reiwa 7 tax year
• The filing deadline may be extended due to special provisions for disasters, etc.
• It is recommended to confirm with a tax office or licensed tax accountant before the final submission
• If a disclaimer notation is required, run /tax-legal-context