Comparison · Email clients
Outlook vs Spark: which is better in 2026?
Spark ranks higher in our list of email clients (#2 against #3, score 88.0 against 87.0), but the gap is small and the better choice depends on what you need.
- 87.0Editorial score88.0
- 5Platforms4
- YesFree to useYes
- NoOpen sourceNo
Which should you choose?
Choose Outlook if you want
Microsoft 365 and Outlook.com users.
Microsoft's mail client for Windows and Mac, with calendar, contacts and To Do in one app and a free web version at Outlook.com. Calendar and mail are tied to the mailbox, and desktop features depend on the account and plan.
Choose Spark if you want
One inbox across phone and desktop.
One app on iOS, Mac, Android and Windows, with a smart inbox that sorts mail by importance. Its code is closed, and its Premium plan adds the paid features.
The main differences
- Only Outlook runs on Web.
Side by side
 Outlook |  Spark | |
|---|---|---|
| Score | 87.0 | 88.0 |
| Rank in list | #3 of 10 | #2 of 10 |
| Price | Free plan, paid upgradesFree web version at Outlook.com; desktop apps and extras depend on plan | Free plan, paid upgradesFree to get started; Spark Premium adds paid features |
| Free to use | Yes | Yes |
| Open source | No | No |
| Platforms | WindowsmacOSiOSAndroidWebWindows, macOS, iOS, Android, Web | iOSmacOSAndroidWindowsiOS, macOS, Android, Windows |
| Made by | Microsoft | Not stated |
| Phone app | Yes | Yes |
| Best for | Microsoft 365 and Outlook.com users | One inbox across phone and desktop |
| Strengths |
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| Limits |
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| Links | Visit site | Visit site |
Questions about Outlook vs Spark
- Is Spark better than Outlook?
- Spark ranks higher in our list of email clients (#2 against #3, score 88.0 against 87.0), but the gap is small and the better choice depends on what you need. Outlook is best for: Microsoft 365 and Outlook.com users. Spark is best for: one inbox across phone and desktop.
- Which is cheaper, Outlook or Spark?
- Outlook: Free web version at Outlook.com; desktop apps and extras depend on plan. Spark: Free to get started; Spark Premium adds paid features.
- Do Outlook and Spark run on the same platforms?
- Outlook supports Windows, macOS, iOS, Android, Web. Spark supports iOS, macOS, Android, Windows.
Choosing between the two
Learning Center
1:17How to decide between two good optionsSettle a close call by sorting it by how hard it is to undo, setting a deadline, scoring the criteria as a tie-breaker and writing down why you chose.
1:20How to compare products fairly: what to keep in mindDefine the job, cap the must-haves, compare like with like, count total cost over one period and weigh the criteria. Includes a worked example.