Microsoft 365.

Microsoft's cloud productivity suite including Teams, Outlook, and Office

Facts

Office.eu
100% European office suite from The Hague, built on open-source (Nextcloud), EU-only data centres
NL · open-source
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ONLYOFFICE
European office collaboration suite with self-hosting option
LV · open-source
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SoftMaker Office
German office suite with strong Microsoft Office compatibility and cross-platform support
DE · commercial
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Nextcloud
Open-source self-hosted collaboration platform for file sync, chat, and office
DE · open-source
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Collabora Online
UK-based enterprise LibreOffice-powered online office suite for self-hosting and cloud
GB · open-source
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Open-Xchange
European open-source email, calendar, and productivity suite
DE · open-source
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Ashampoo Office
German office suite with word processing, spreadsheets and presentations, Microsoft format compatible
DE · commercial
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Kopano
Dutch groupware with self-host options
NL · open-source
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