# Mailspring vs Proton Mail

**Leader by vioscaleAI score:** Proton Mail

| Attribute | Mailspring | Proton Mail |
|---|---|---|
| **vioscaleAI score** | 58.5 (65% (medium)) | 75 (72% (medium)) |
| activity.commits_last_30d | 100 | - |
| adoption.github_stars | 17,885 | - |
| content.faq | `[{"answer":"A lightweight desktop application for Mac, Windows, and Linux that brings together multiple email accounts from different providers into one unified inbox. Core features run locally on your computer, with optional paid features for message tracking, scheduling, and productivity analytics. It is indexed under Email Clients.","source":"https://getmailspring.com","question":"What is Mailspring?","confidence":0.6},{"answer":"Mailspring is open source, so it can be self-hosted and used at no licence cost. It is released under the GPL-3.0 licence. A commercial or hosted edition starts at $8 per month. Prices are published openly on the vendor's own pricing page. Pricing changes often, so verify at source before relying on it.","source":"https://getmailspring.com","question":"Is Mailspring free to use?","confidence":0.6},{"answer":"Mailspring supports Windows, macOS and Linux. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://getmailspring.com","question":"What platforms does Mailspring support?","confidence":0.6},{"answer":"We have confirmed 8 integrations for Mailspring, including Gmail, iCloud, Office 365, FastMail, Outlook.com, Yahoo!, IMAP and SMTP. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://getmailspring.com","question":"What does Mailspring integrate with?","confidence":0.6},{"answer":"Yes. Mailspring is published under the GPL-3.0 licence, a copyleft licence, so check its terms before embedding it in a closed-source product. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/foundry376/Mailspring","question":"Is Mailspring open source?","confidence":0.95}]` | `[{"answer":"An email platform using zero-access encryption so the provider cannot read messages, funded by subscriptions rather than data exploitation. It is indexed under Email Clients.","source":"https://proton.me/business/pass/pricing","question":"What is Proton Mail?","confidence":0.6},{"answer":"Proton Mail offers a free tier, so you can start without paying. Paid plans are also available: Pass Essentials, Pass Professional, VPN and Pass Professional and Workspace Standard. Pricing changes often, so verify at source before relying on it.","source":"https://proton.me/business/pass/pricing","question":"Is Proton Mail free?","confidence":0.6},{"answer":"Proton Mail supports the web, Windows, macOS, Linux, iOS, Android and a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://proton.me/business/pass/pricing","question":"What platforms does Proton Mail support?","confidence":0.6},{"answer":"We have only confirmed a cloud / SaaS deployment for Proton Mail, so it appears to be vendor-hosted. If a self-hosted option exists we have not found it documented publicly.","source":"https://proton.me/business/pass/pricing","question":"Can Proton Mail be self-hosted?","confidence":0.6},{"answer":"We have confirmed 11 integrations for Proton Mail, including Gmail, Outlook, Yahoo, Apple Mail, Thunderbird, Google, Okta and Microsoft Entra ID, plus 3 more. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://proton.me/business/pass/pricing","question":"What does Proton Mail integrate with?","confidence":0.6},{"answer":"We have independently confirmed SOC 2, ISO 27001, HIPAA and GDPR for Proton Mail. Certifications we do not list are ones we have not been able to verify from public sources, which is not the same as Proton Mail not holding them. Always confirm compliance directly before you rely on it.","source":"https://proton.me/nb/business/mail/security","question":"What security certifications does Proton Mail have?","confidence":0.7},{"answer":"Proton Mail is available worldwide. Its primary markets are the EU, the United States and the United Kingdom. The vendor is headquartered in Switzerland.","source":"https://proton.me/business/pass/pricing","question":"Where is Proton Mail available?","confidence":0.75}]` |
| deployment.options | `{"self_hosted":true}` | `{"cloud":true}` |
| description.long | Mailspring is a desktop email client built as open source that runs your sync engine locally without sending credentials to remote servers. It includes core features like unified inbox, snooze, scheduled sending, and mail rules, with optional premium capabilities available through a paid subscription. | A cloud-based email platform using end-to-end encryption to keep all messages private from Proton and advertisers, funded by subscriber revenue. It provides a permanent free tier with core email functionality, plus paid plans offering enhanced storage, custom domains, and integrated business services. |
| features.capabilities | `{"pricing_model":"freemium","deployment_model":"local_direct_imap_client","read_receipts_and_open_tracking":true,"snooze_and_scheduled_send_later":true,"unified_multi_account_inbox_view":true,"universal_imap_smtp_exchange_support":true}` | `{"iso_27001":true,"soc2_type_ii":true,"pricing_model":"freemium","deployment_model":"cloud_synchronization_proxy","conversational_chat_layout_view":false,"read_receipts_and_open_tracking":false,"snooze_and_scheduled_send_later":true,"generative_ai_llm_email_drafting":true,"unified_multi_account_inbox_view":true,"pgp_end_to_end_encryption_support":true,"split_inbox_ai_auto_categorization":false,"universal_imap_smtp_exchange_support":true,"keyboard_shortcut_only_navigation_speed":false}` |
| integrations.count | 7 | 7 |
| integrations.list | `[{"name":"Gmail"},{"name":"iCloud"},{"name":"Office 365"},{"name":"FastMail"},{"name":"Outlook.com"},{"name":"Yahoo!"},{"name":"IMAP"},{"name":"SMTP"}]` | `[{"name":"Gmail"},{"name":"Outlook"},{"name":"Yahoo"},{"name":"Apple Mail"},{"name":"Thunderbird"},{"name":"Google"},{"name":"Okta"},{"name":"Microsoft Entra ID"},{"name":"ADFS"},{"name":"Edugain"},{"name":"SimpleLogin"},{"name":"Yahoo Mail","native":false,"category":"email","direction":"inbound"},{"name":"Chrome","native":false,"direction":"bidirectional"},{"name":"Firefox","native":false,"direction":"bidirectional"}]` |
| language.primary | TypeScript | - |
| license.spdx | GPL-3.0 | - |
| market.availability | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` | `{"primaryMarkets":[],"availabilityScope":"global","availableCountries":[],"notAvailableCountries":[]}` |
| platform.support | `{"mac":true,"linux":true,"windows":true}` | `{"cli":true,"ios":true,"mac":true,"web":true,"linux":true,"android":true,"windows":true}` |
| pricing | `{"type":"hybrid","plans":[{"free":true,"name":"Free","features":["Unified Inbox","Snooze","Send Later","Mail Rules","Templates"],"description":"Open source version with core email features","contactSales":false},{"free":false,"name":"Mailspring Pro","features":["Link tracking","Read receipts","Mailbox analytics","Contact profiles","Company profiles"],"commitment":"monthly","description":"Premium subscription unlocking additional features","contactSales":false}],"summary":"Free open source core + monthly paid Pro tier","freeTier":true,"sourceUrl":"https://getmailspring.com","retrievedAt":"2026-10-05T10:08:40.523Z","billingPeriods":["month"]}` | `{"type":"freemium","plans":[{"free":true,"name":"Free","summary":"Free forever","features":["End-to-end encryption","Email and calendar access"],"components":[{"kind":"fixed","amount":0,"period":"month","currency":"USD"}],"description":"Basic email functionality with the same encryption and security as paid plans","contactSales":false},{"free":false,"name":"Workspace Standard","summary":"$12.99/user/month, billed annually at $155.88","features":["1 TB cloud storage","15 custom email domains","VPN access for 10 devices","25 booking pages","Password manager","Collaborative document editing"],"commitment":"annual","components":[{"kind":"fixed","amount":12.99,"period":"month","currency":"USD"}],"description":"All Proton products bundled including email, storage, VPN, and collaboration tools for teams","contactSales":false,"includedLimits":{"storage":"1 TB per user","calendars":"25","custom_domains":"15"}}],"summary":"Free tier available. Paid plans starting at $12.99/user/month for business bundles.","currency":"USD","freeTier":true,"sourceUrl":"https://proton.me/business/pass/pricing","retrievedAt":"2026-10-12T16:05:55.600Z","startingPrice":{"amount":12.99,"period":"month","currency":"USD"},"billingPeriods":["month","year"]}` |
| pricing.free_tier | yes | yes |
| pricing.model | freemium | freemium |
| pricing.price_level | low | low |
| pricing.starting_price | `{"amount":8,"currency":"USD"}` | `{"amount":12.99,"currency":"USD"}` |
| pricing.transparent | no | yes |
| release.cadence_days | 12 | - |
| release.history | `[{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.26.0","date":"2026-10-02T14:37:36Z","type":"stable","version":"1.26.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.25.0","date":"2026-09-19T22:57:29Z","type":"stable","version":"1.25.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.24.1","date":"2026-09-15T02:13:24Z","type":"stable","version":"1.24.1"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.24.0","date":"2026-09-13T01:27:57Z","type":"stable","version":"1.24.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.23.0","date":"2026-07-22T03:45:22Z","type":"stable","version":"1.23.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.22.0","date":"2026-06-13T20:30:13Z","type":"stable","version":"1.22.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.21.1","date":"2026-05-20T20:31:26Z","type":"stable","version":"1.21.1"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.21.0","date":"2026-05-06T13:40:43Z","type":"stable","version":"1.21.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.20.1","date":"2026-04-20T16:07:46Z","type":"stable","version":"1.20.1"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.20.0","date":"2026-04-19T03:40:03Z","type":"stable","version":"1.20.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.19.1","date":"2026-04-07T01:34:03Z","type":"stable","version":"1.19.1"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.19.0","date":"2026-03-10T04:46:53Z","type":"stable","version":"1.19.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.18.0","date":"2026-02-23T14:40:58Z","type":"stable","version":"1.18.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.17.4","date":"2026-02-11T16:59:03Z","type":"stable","version":"1.17.4"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.17.3","date":"2026-01-31T20:21:11Z","type":"stable","version":"1.17.3"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.17.2","date":"2026-01-24T21:09:28Z","type":"stable","version":"1.17.2"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.17.1","date":"2026-01-15T20:55:25Z","type":"stable","version":"1.17.1"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.17.0","date":"2026-01-14T22:33:16Z","type":"stable","version":"1.17.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.16.0","date":"2025-07-16T14:29:44Z","type":"stable","version":"1.16.0"},{"url":"https://github.com/Foundry376/Mailspring/releases/tag/1.15.1","date":"2025-01-27T00:52:05Z","type":"stable","version":"1.15.1"}]` | - |
| reliability.sla_pct | - | 99.95 |
| security.certifications | - | `[{"name":"ISO 27001","status":"active"}]` |
| security.gdpr | - | yes |
| security.hipaa | - | yes |
| security.iso27001 | - | yes |
| security.pci | - | yes |
| security.soc2 | - | yes |
| security.trust_center | - | https://proton.me/nb/business/mail/security |

## Capabilities (Email Clients)

| Capability | Mailspring | Proton Mail |
|---|:--:|:--:|
| **Capabilities** |  |  |
| Deployment model | Local direct imap client | Cloud synchronization proxy |
| Universal imap smtp exchange support | ✓ | ✓ |
| Keyboard shortcut only navigation speed | - | ✗ |
| Split inbox AI auto categorization | - | ✗ |
| Read receipts and open tracking | ✓ | ✗ |
| Snooze and scheduled send later | ✓ | ✓ |
| Generative AI LLM email drafting | - | ✓ |
| Conversational chat layout view | - | ✗ |
| Unified multi account inbox view | ✓ | ✓ |
| Pgp end to end encryption support | - | ✓ |
| SOC2 type ii | - | ✓ |
| ISO 27001 | - | ✓ |
| Pricing model | Freemium | Freemium |

*Source: vioscaleAI. Generated 2026-10-16T19:27:52.905Z. "-" = undocumented, not absent.*
