If your business is choosing between Slack and Microsoft Teams in 2026, the answer usually comes down to one question: are you already on Microsoft 365? If yes, Teams is included in what you’re already paying for, and switching away costs money without solving a problem. If no, or if your team culture is closer to a startup than a professional services firm, Slack still has a fair case to make. This article walks through the honest side-by-side on price, features, security, and what “switching” actually looks like, from the perspective of an MSP that spends most of its week inside Microsoft 365 tenants.
The short verdict: Who each tool is for
Both tools do the same core job: team chat, video calls, file sharing, and integrations with the rest of your stack. Where they diverge is philosophy.
- Microsoft Teams is built as part of the Microsoft 365 platform. It assumes you’re using Outlook, SharePoint, OneDrive and Word. The strength is that everything is one identity, one bill, one place to secure, and one team to support. The weakness is that if you’re not on M365, Teams is a much harder sell.
- Slack is built as an independent chat platform first, integrations second. The strength is that it’s fast, flexible, and works cleanly with hundreds of third-party tools (Notion, Linear, GitHub, Zapier). The weakness is that you’re paying extra for chat on top of whatever else you’re already paying for: email, files and calendars.
For Australian professional services firms with 10 to 200 users, Teams wins somewhere around 9 out of 10 times, because 9 out of 10 of those firms are already on Microsoft 365. The rest of this article is where the numbers actually land, and where Slack still has an argument.
Price: what each will actually cost you
Both platforms have free tiers with meaningful limits. The comparison that matters is between the paid plans your business will actually use.
- Microsoft Teams: Comes bundled with every Microsoft 365 Business plan (Basic, Standard, Premium) and every Enterprise plan (E3, E5). If your business is on M365 already, Teams costs you nothing extra. Teams Essentials as a standalone product runs around $6 per user per month (AUD) if you don’t want the rest of the M365 stack.
- Slack: Pro is around $12–13 per user per month; Business+ is around $22–23 per user per month; Enterprise Grid is custom-quoted. Slack does not include email, calendar, file storage or word processing. Those are separate subscriptions on top.
Practical example. A 50-person firm on Microsoft 365 Business Standard already pays around $21 per user per month for the full M365 stack including Teams. Add Slack Pro on top, and you’re looking at an extra $7,500 a year for a chat tool that duplicates something you already own. Add Slack Business+, and it’s $13,800 a year. That maths does most of the deciding for professional services firms.
Features that actually matter for day-to-day work
Both tools cover the essentials. The differences show up in the details.
- Chat and channels: Slack’s channel model is cleaner and more intuitive for teams who live in chat. Teams is closing the gap fast, and its channel-per-project model works well when the project also has files, meetings and a shared plan attached.
- Video calls and meetings: Teams wins here for anyone doing meetings with clients. Native calendar invites through Outlook, background blur and effects, live captions, meeting recording with transcription, and Copilot summaries all work out of the box. Slack Huddles and video calls are fine for internal use but noticeably less polished for client-facing calls.
- File sharing and co-authoring: Teams integrates natively with SharePoint and OneDrive, so a file shared in Teams is a file you can co-edit in Word or Excel with proper version history. Slack shares files through a separate system that doesn’t play as well with document editing.
- Search and history: Both have good search on paid plans. Slack’s free tier caps message history at 90 days, which is a real limitation for professional services firms who need audit trails.
- AI features: Teams ships with Copilot integration across Word, Excel, Outlook and Teams itself (with the M365 Copilot add-on). Slack has AI features on Business+ and above, focused on summarising channels and threads. For businesses already investing in AI-assisted work, Teams sits closer to the rest of the stack.
Integrations with your existing tools
This is the one area where Slack still has a clear edge, and it matters if your team relies on it.
Slack integrates deeply with developer and creative tools (GitHub, GitLab, Linear, Notion, Figma, Zapier, dozens of niche SaaS products). If your team lives in those tools, Slack’s channel-based notifications and slash commands are genuinely better than the Teams equivalents.
Teams integrates deeply with the Microsoft ecosystem (Outlook, SharePoint, OneDrive, Planner, Power BI, Dynamics, Loop). Third-party integrations exist but are less mature than Slack’s equivalents. That said, if most of your business runs on Microsoft’s tools already, you don’t need the third-party bridge, because the first-party integrations do the same job with one login and one security policy.
Rough rule of thumb: developer-heavy or creative-agency teams benefit from Slack’s integration depth. Professional services firms (legal, medical, accounting, consulting) get more value from the Microsoft-native integrations because that’s where their work actually lives.
Security, compliance and the Australian context
For businesses handling client data, this is where the decision often gets made.
- Identity and access: Both platforms support multi-factor authentication and single sign-on. Teams uses Microsoft Entra ID (same identity as your Microsoft 365 accounts), which means one MFA setup, one conditional access policy, and one place to disable an ex-employee. Slack sits on its own identity system unless you connect it to Okta, Google Workspace or Entra ID, which is fine but adds work to maintain.
- Data location: Teams data for Australian tenants sits in Australian Microsoft data centres. Slack stores customer data in the US by default; Enterprise Grid customers can pay for data residency in select regions, but Australia is not always one of them.
- Compliance and audit: Both platforms support the compliance certifications most Australian businesses need. But if you’re already under obligations that push you toward tighter controls (RACGP standards for medical practices, LPCC guidance for legal firms, APRA CPS 234 for financial services), running one platform (Microsoft 365 with Teams) is materially simpler than running two platforms (Microsoft 365 for email and files, Slack for chat) with two audit trails and two DLP configurations. Our managed security services practice sees this trade-off constantly with Australian professional services clients.
- Data Loss Prevention: Microsoft Purview DLP policies cover Teams, Exchange, SharePoint, OneDrive and Word in one policy engine. Slack DLP requires third-party tools or Enterprise Grid, which prices most SMEs out.
For a professional services business, “same identity, same DLP, same audit log across email, files and chat” is a real operational advantage, not a marketing line.
When Slack is actually the better choice
Teams doesn’t win every scenario. Slack is the better call when:
- Your team is developer- or creative-heavy and lives inside third-party tools that have first-class Slack integrations (GitHub, Linear, Figma, Notion).
- You’re not on Microsoft 365 and don’t want to be. If you’re a Google Workspace shop with no plan to switch, Teams is a much harder fit; Slack integrates with Google Workspace far better than Teams does.
- Chat culture matters more than enterprise integration. Small, fast-moving teams (agencies, SaaS startups, product teams) often find Slack’s UX more natural, and the productivity difference is real for that kind of workflow.
- You’ve already invested heavily in Slack with custom bots, workflow automations, and integrations that would be expensive to rebuild in Teams. Migration cost is a real number.
For the businesses CRT typically works with (10- to 200-user professional services firms across Brisbane and the Sunshine Coast), those criteria rarely apply. But if they do, Slack is the honest answer.
What “moving from Slack to Teams” actually involves
If the answer for your business is Teams and you’re currently on Slack, the switch is usually smaller than it looks. Slack does not natively export directly into Teams, but there are two working paths.
- Chat migration tools (Migrate Wizard, ShareGate, or Microsoft’s built-in Slack import for Teams) can move channels, message history, users, and files across in a controlled way. The tool choice depends on your Slack plan and how much history you want to preserve.
- Fresh-start migration: Freeze the Slack workspace to read-only, stand up Teams with the same channel structure, and run both in parallel for two to four weeks while the team acclimatises. This is cheaper and often easier than a full data migration if your Slack history isn’t legally required.
The bigger project is usually not the chat itself but the surrounding change management: rebuilding integrations, retraining the team, and configuring Teams to match how your business actually works. If you’re already using Microsoft 365 Setup or planning a broader Microsoft 365 rollout, folding the Slack-to-Teams switch into that work is usually the smart move rather than doing them separately.
Frequently Asked Questions
Is Microsoft Teams free with Microsoft 365?
Yes. Every Microsoft 365 Business plan (Basic, Standard, Premium) and Enterprise plan (E3, E5) includes Teams at no extra cost. If your business is already paying for M365, adding Teams costs you nothing. Standalone Teams Essentials (without the rest of M365) currently runs around $6 per user per month for businesses that want chat and video only.
Can we run both Slack and Teams at the same time?
Technically yes, but it’s rarely a good idea long-term. Two chat platforms mean two places to search for a conversation, two identity systems to maintain, two audit trails, and two subscriptions to justify. Some businesses run both temporarily during a migration; almost none should run both permanently unless there’s a very specific team-by-team reason.
What about data sovereignty for Australian businesses?
Microsoft 365 (including Teams) stores Australian tenant data in Australian data centres, which is often required for government contracts and preferred by healthcare, legal and financial services firms. Slack stores customer data in the US by default. Data residency options exist for Slack Enterprise Grid customers, but Australia is not always in the supported list. For Privacy Act-covered businesses, this is worth confirming before signing.
How long does a Slack to Teams migration take?
For a 50-user firm with straightforward Slack usage, a full migration usually takes two to four weeks of elapsed time, with most of the work being planning, communication and configuration rather than technical data transfer. Larger tenants (200+ users) with heavy Slack integrations can take six to eight weeks. If chat history preservation isn’t a legal requirement, a fresh-start migration can be done in a week.
Get in touch
If you’re weighing Slack against Microsoft Teams and want a straight second opinion on which fits your business, we can help. CRT works with Australian professional services businesses across Brisbane and the Sunshine Coast to run Microsoft 365 Setup, tenant hardening and ongoing support. Call 1300 760 339 or request a quote online.
