★★★★★ OSS
End-to-end encrypted email under Swiss jurisdiction. Zero-access design means Proton cannot read your plaintext mail.
- E2EE
- Proton Calendar/Drive/VPN連携
- Hide-my-email
- Tor対応
⚠ 無料枠1GB
なぜ Gmail から離れる？
Your email address is core ID for banks, social networks, and government. Gmail suspension means losing contact; policy changes and AI processing add long-term risk. A provider you can choose—with encryption and jurisdiction you control—is the first step to digital independence.
Googleの限界・リスク
- • Google account suspension or lockout can take your email address with it
- • Ad scanning ended in 2017, but content is still processed for security, smart features, and AI summaries
- • Free 15 GB is shared with Drive and Photos and fills quickly for long-term storage
- • IMAP/POP restrictions on free accounts limit freedom with other clients
- • Data center location and government requests follow Google policy—you cannot choose
- • Custom domains require paid Workspace—poor fit for a portable personal address strategy
選び方ガイド
全部試す必要はありません。あなたの優先順位に合わせて絞り込みましょう。
- 1 For E2EE first: Proton Mail or Tutanota—Swiss/German jurisdiction and zero-access encryption
- 2 For IMAP, Thunderbird, and existing workflows: Fastmail, Mailbox.org, or Posteo
- 3 For cheap multi-address custom domain: Migadu
- 4 Apple-centric seamless setup: iCloud Mail (watch ecosystem lock-in)
- 5 Skiff was acquired by Notion in 2024—listed for historical reference only
- 6 Business compliance: Mailbox.org or Posteo under German GDPR
クイック比較
プライバシー・使いやすさ・機能・コスパの4軸で評価しています。
| ツール | Privacy | Ease of use | Features | Value | 総合 |
|---|---|---|---|---|---|
| Proton Mail | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 16/20 |
| Tutanota | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 16/20 |
| Fastmail | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 18/20 |
| Migadu | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 15/20 |
| Mailbox.org | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 16/20 |
| Posteo | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 17/20 |
| Skiff | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 14/20 |
| iCloud Mail | ★★★★★ | ★★★★★ | ★★★★★ | ★★★★★ | 17/20 |
すべての代替ツール（8）
★★★★★ OSS
German fully encrypted email (subjects and contact lists included). GDPR-compliant with no ads or tracking.
- 全体暗号化
- GDPR準拠
- カレンダー内蔵
- whitelabel for business
⚠ 標準IMAP/SMTP非対応
★★★★
Ad-free paid email from Australia with full IMAP/SMTP, excellent UI, custom domains, and powerful filters.
- 広告なし
- カスタムドメイン
- 優れたモバイルアプリ
- スヌーズ・スケジュール送信
⚠ 完全E2EEではない
★★★★
Email hosting built for your own domain. Flat pricing, simple admin, full IMAP/SMTP—no per-user metering.
- 独自ドメイン必須
- 従量課金なし
- 低価格
- 無制限エイリアス（実質）
⚠ ドメイン取得が別途必要
★★★★★
German privacy-focused hosting: mail plus calendar, contacts, and cloud storage. GDPR-compliant with optional PGP.
- GDPR準拠
- PGPサポート
- カレンダー/連絡先/ストレージ
- 緑の電力DC
⚠ UIはやや旧式
★★★★★
Nonprofit-oriented Berlin provider. Anonymous signup, no ads, IMAP/SMTP, calendar and contacts. Strong environmental ethics.
- 匿名登録可
- 広告なし
- グリーンエネルギー
- オプション暗号化ストレージ
⚠ カスタムドメイン非対応（@posteo.deのみ）
★★★★
E2EE mail, docs, and storage in one service. Acquired by Notion in February 2024; new signups are closed (historical reference only).
- E2EEメール
- ドキュメント統合
- Web3ログイン対応（当時）
- モダンUI
⚠ 2024年Notion買収・新規登録停止
★★★★
Apple cloud mail at @icloud.com or custom domains (iCloud+). Deep device integration; Advanced Data Protection enables stronger E2EE.
- Apple統合
- Hide My Email
- Advanced Data Protection
- カスタムドメイン（iCloud+）
⚠ Apple端末が前提
移行のヒント
- 1 Get a custom domain (example.com) so you can change providers later
- 2 Export from Gmail via Takeout or IMAP (Thunderbird + ImportExportTools NG)
- 3 Update registered emails on important services; keep Gmail forwarding for a transition period
- 4 Enable 2FA and backup codes on the new service
- 5 Configure SPF, DKIM, and DMARC per your new provider’s DNS guide