Overview

Group-Office is open-source software from a maker founded in 2003 and based in ’s-Hertogenbosch, Netherlands. Its scope reaches well beyond email and calendars: teams can manage customer records, projects, documents, support requests and invoicing in one product. That breadth may reduce the need to coordinate separate tools, but organizations seeking only a focused project tracker or CRM may find the combined scope unnecessary.

Teams can run it on their own server or use the hosted service, which the company says is hosted in the Netherlands. The choice matters: self-hosting offers deployment control, while Online avoids running a server but charges by the month and limits storage per user.

Key features

Collaboration and documents

Users can co-edit documents, schedule meetings and communicate by chat or video call. File management and document editing integrate with OnlyOffice, Collabora Online and Office 365. The combination is useful for teams that need shared workspaces alongside communication, though Online charges extra for its document editor, video calls and chat.

CRM, projects and finance

CRM includes shared address books, newsletters and support tickets submitted through a website or email. Project tools cover task and file tracking, time tracking, reporting, and invoicing for project work and time. Finance supports online payments through services including Mollie and PayPal, plus e-invoicing formats ZUGFeRD, XRechnung and UBL. This is a substantial range for a team looking to connect customer work to delivery and billing, but the paid-plan boundaries matter: Professional adds projects, time tracking, support tickets and newsletters, while Online charges separately for finance.

Sync, customization and security

Group-Office synchronizes email, contacts, calendars, notes and tasks with native apps on iOS, macOS, Android and Windows devices. It uses IMAP, Microsoft ActiveSync, CalDAV, CardDAV and WebDAV, giving teams several familiar sync protocols. Custom fields, filters and GroupOffice Studio, which lets power users build modules, make the product more adaptable to internal processes; Studio is included in Professional.

The privacy policy describes SSL encryption, one-time-password two-factor authentication, fail2ban, IP address access control and regular security tests. The provider says its services and daily offsite backups are in the Netherlands, with backups kept for 14 days. These are useful safeguards and a defined recovery window, though they do not replace a team's own assessment of its security and continuity needs.

Pricing

Group-Office is freemium, with a free plan, a 30-day trial and paid options from €12/mo. The different billing terms and add-on charges make it important to compare the actual deployment and feature set, not just the starting price.

Community: 0.00 EUR per free for unlimited users. The self-hosted Community edition includes email, calendar, files, document editing, notes, tasks, chat and video calls, address book and device sync. It is a strong starting point for teams able to host and administer the software; it does not include the Professional plan’s stated paid features such as projects, time tracking, newsletters, Kanban, Studio and helpdesk support.
Professional (self-hosted): 439.00 EUR per once for a perpetual license covering 1–100 users, with updates costing €219 per year. It adds support tickets, time tracking, projects, newsletters, Kanban, Studio and helpdesk support from 9 to 5 CET/CEST. This suits organizations that want the richer feature set on their own server and can work within the 100-user ceiling. The annual updates charge is separate from the license.
Professional: 439.00 EUR per month, billed Perpetual License, for 1–100 users; Professional updates cost 219.00 EUR per year. Because the license and updates are separate charges, budget for both when keeping Professional features current.
Online: 12.00 EUR per month, with 5 GB storage per user and helpdesk from 9 to 5 CET. Document editor, video call and chat each cost €2/user; Finance costs €12/install and Document Search €15/install. It fits teams that prefer hosted service, but the per-user storage allowance and feature add-ons can raise the cost as usage grows. Extra storage is offered in monthly blocks.
Billing add-on: 219.00 EUR per once for invoices, online payments and smart debtor profiles. This brings billing capabilities to teams that need them without describing an ongoing charge.
Document Search add-on: 299.00 EUR per once for deep file-content search, metadata search and E-Discovery.

Service contracts list weekday phone support from 9 to 17. That may matter to organizations needing a direct support channel, alongside the helpdesk terms attached to Professional and Online.

Platforms

Group-Office supports Android, iOS, Linux, macOS, Windows, web and self-hosted deployment, and it has a mobile app. Native-device synchronization across the listed mobile and desktop systems makes it a plausible fit for mixed-device teams rather than organizations tied to one operating system.

Who it's for

Group-Office is best suited to organizations that want collaboration, CRM and project work together, especially those that value open-source software, self-hosting or avoiding per-user fees on the Community edition. Professional is the more complete self-hosted choice for teams within its 100-user range that need project and support functions. Online is the more direct route for teams that want hosted service, provided 5 GB per user and the extra charges for selected tools fit their budget. It is less compelling for teams that need a large hosted storage allowance or expect to use every paid feature without add-on costs.

Pros and cons

Pro: The free self-hosted Community edition supports unlimited users and includes a broad baseline of communication, document and device-sync tools, avoiding an entry-level per-seat charge.
Pro: CRM, project tracking, time reporting and invoicing sit alongside collaboration features, making it useful for teams that want customer and delivery work in one system.
Pro: Self-hosting and a hosted option accommodate different deployment preferences; the provider says its hosted service and 14-day daily offsite backups are in the Netherlands.
Con: Professional covers only 1–100 users and has a separate annual updates charge, so larger teams or those budgeting for ongoing updates need to account for those terms.
Con: Online's 5 GB per-user storage limit can constrain document-heavy teams, and its editor, video calls, chat and finance carry extra charges.
Con: Community lacks several functions called out for Professional, including projects, time tracking, newsletters and Studio, so teams needing those capabilities face a paid step up.

Alternatives

For a narrower project-management shortlist, compare Project Management Software; for document-focused needs, see Document Management Software; and for customer-management priorities, browse CRM Software.

Nifty is worth considering when project management is the priority: its free plan allows unlimited members but limits storage to 100 MB and active projects to two.
PLANKA is an alternative for teams seeking a self-hosted project-management tool, with a free Community edition and a Pro Self-Hosted plan at 36.00 EUR per mo.
Agantty may suit a team focused on a single project: its free plan allows one project, with no teams or support.
Basecamp is another option for teams that can work within its free plan's one-project, 1 GB storage and five-user limits.
Hive may be a better fit for a team seeking a task-oriented workspace; its free plan includes unlimited tasks and up to 10 workspace members, with 200 MB storage.
MeisterTask is an alternative for teams whose needs fit its free plan's limit of three projects and five Content Manager seats.
ClickUp offers a free option with unlimited tasks and free-plan members, though storage is limited to 60 MB.
ProjectLibre is an alternative for readers comparing project-management tools.

Verdict

Choose Group-Office if you want open-source groupware that can span CRM, collaboration and project work, and you value either self-hosting or a Netherlands-hosted option. Its unlimited-user Community edition is an unusually broad starting point, while Professional adds substantial team and business functions. Look elsewhere if your team needs more than 5 GB per user on a hosted plan, wants paid capabilities without add-on charges, or exceeds Professional's 100-user limit.

	Group-Office	Hassl
Free plan	Yes	No
Free trial	Yes
Paid from	€12/mo	$6/mo
Open source	Yes
Platforms	Android, iOS, Linux, macOS, self-hosted, Web, Windows	Web
Free plan	Yes	No
Free trial	Yes
Mobile app	Yes
Open source	Yes
Paid from		6 /user/mo
Automation rules		Yes
Time tracking		Yes
Guest access		Yes

Group-Office vs Hassl

Group-Office

Hassl