Mozilla Thunderbird vs eM Client

Mozilla Thunderbird9.4Visit eM Client8.8Visit

Higher score Mozilla Thunderbird #1 in Email Clients 9.4/10 Free plan Free plan✓ 4 of 4 features Visit Thunderbird

vs

eM Client #6 in Email Clients 8.8/10 Free plan · 30-day trial Free planFree trial✓ 4 of 4 features Visit eM Client

• Mozilla Thunderbird fits best

  Users wanting a free, established open-source client

• eM Client fits best

  Users wanting broad productivity integrations

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Side by side

Feature	Mozilla Thunderbird 9.4/10 Visit ↗	eM Client 8.8/10 Visit ↗
At a glance
Editor score	9.4	8.8
Ranking	#1 in Email Clients	#6 in Email Clients
Best for	Users wanting a free, established open-source client	Users wanting broad productivity integrations
Pricing model	Free	Free plan + paid
Starting price	Free	$39.95/user/yr
Free plan	✓	✓
Free trial	—	30 days
Deployment	Desktop, Mobile	Desktop, Mobile
Platforms	Windows, macOS, Linux, Android	Windows, macOS, iOS, Android
Support	Community, Docs	Email, Community
Built for	Solo, Small business, Mid-market, Enterprise	Solo, Small business, Mid-market, Enterprise
Features Mozilla Thunderbird 4/4 · eM Client 4/4
Unified inbox	✓	✓
Offline access	✓	✓
Scheduled sending	✓	✓
Calendar tools	✓	✓
Specs
App coverage	Not checked yet	All
Account limit	Not checked yet	2 accounts
Our review
Pros	Unified inbox for managing multiple email accounts Calendar, contacts, and tasks included in the Free plan Offline access, local synchronization, and add-on extensibility	Unified inbox supports multiple email accounts Works across Windows, macOS, iOS and Android Includes encryption, offline access, calendars and AI assistance
Cons	No verified integrations are listed Send Later is a queue, not timed scheduled delivery Mobile availability is limited to Android	Free license is limited to two email accounts Free license is for personal, non-commercial use Its broad feature set may exceed email-only needs
Our verdict	Mozilla Thunderbird is a free, open-source email client for personal and business use. It supports multiple email accounts, unified inboxes, message search and organization, calendars, contacts, and tasks. The desktop application is… Read the review →	eM Client is an email client for individuals, freelancers and businesses who want email, calendars, tasks, contacts, notes and chat in one application. It connects with Gmail, Google Workspace, Microsoft 365, Exchange, Outlook, iCloud,… Read the review →

Strengths and trade-offs

• Mozilla Thunderbird — where it wins

  • Unified inbox for managing multiple email accounts
  • Calendar, contacts, and tasks included in the Free plan
  • Offline access, local synchronization, and add-on extensibility

  Where it doesn't

  • No verified integrations are listed
  • Send Later is a queue, not timed scheduled delivery
  • Mobile availability is limited to Android

• eM Client — where it wins

  • Unified inbox supports multiple email accounts
  • Works across Windows, macOS, iOS and Android
  • Includes encryption, offline access, calendars and AI assistance

  Where it doesn't

  • Free license is limited to two email accounts
  • Free license is for personal, non-commercial use
  • Its broad feature set may exceed email-only needs

• Mozilla Thunderbird9.4/10 · Free plan

  A capable free client for multi-account email, offline access, and desktop productivity tools.

  Visit ThunderbirdFull verdict →
• eM Client8.8/10 · Free plan · 30-day trial

  A capable multi-account client for users who want email alongside broader productivity tools.

  Visit eM ClientFull verdict →