In detail: Exchange Online: Via the Office 365 Suite

Which version of Exchange Online is included with Office 365?

Well, it depends which Plan you go for, see the options below.

Office 365 (Plan E1)	Office 365 (Plan E2)	Office 365 (Plan E3)	Office 365 (Plan E4)
Exchange Online (Plan 1)	Exchange Online (Plan 1)	Exchange Online (Plan 2)	Exchange Online (Plan 2)

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