Microsoft Teams vs Slack in 2026: Pricing, Free Plans and AI

Pick Microsoft Teams if your team already lives in Outlook, Word and Excel, or you need long meetings with lots of people: Teams Essentials starts at $4 per user per month, paid yearly. Pick Slack if your work runs on channels and tools from many companies. Slack Pro is $7.25 per user per month, paid yearly.

It feels like a big decision, because whichever app you pick is where your team will talk all day, and moving later is a real project. So I'll stick to what actually differs: the free plans, what you'd pay, meetings, working with people outside your company, apps, AI, and the security features you get on each plan. Then I'll tell you which one I'd pick in a few common situations, and what switching from one to the other really involves.

Teams vs Slack: the quick answer

If you only read one row, make it the last one. My rule of thumb: the tool your company already pays for wins, unless people genuinely struggle with it. A second chat app is a second place to miss a message, and that costs more than the license.

Is Slack or Microsoft Teams free?

Both have a free version, and they're limited in very different places.

What Slack Free includes

Slack's plans and features page lists the Free limits:

• 90 days of history. You can see and search the last 90 days of messages and files. Slack's free-plan limits page adds that data more than a year old is deleted.
• Up to 10 apps. That counts third-party and custom apps together.
• One-to-one huddles only. A huddle on Free has a maximum of two people.
• No guests, and Slack Connect only in one-to-one DMs. Slack says guests are only available on paid plans.
• No AI summaries. Conversation summaries and huddle notes start on Pro.

The 90-day window is the one that bites. Say your team picked a printing vendor in March. By July, nobody on Free can scroll back and find out why, and somebody will reopen the whole debate.

What Microsoft Teams (free) includes

Microsoft's free Teams page lists one-to-one calls for up to 30 hours, group calls and meetings for up to 60 minutes, up to 100 people per meeting, and 5 GB of cloud storage per user. Microsoft pitches it mainly for personal use, though it says small businesses and nonprofits can use it too and points them to the business plans for more.

So for a tiny team, Teams free is better for meetings and Slack Free is better for ongoing written work. Picture Megan, who runs a three-person design studio in Denver with two freelancers. Slack Free is fine for the daily back-and-forth about a client's logo, and a free Teams meeting covers a 45-minute review with the client. The day she hires her first full-time designer, I'd have her pay for one or the other. Neither free plan is what I'd run a growing company on.

Slack vs Teams pricing in 2026

These are the list prices on Slack's pricing page and Microsoft's Teams plans page today. Taxes and promotions change what you'll actually pay.

Two things worth knowing before you compare these line by line. First, Business Basic isn't just chat. You get email and Office apps too, so if you'd otherwise pay for those separately, the real comparison is Slack plus your email provider against one Microsoft bill. Second, Slack only counts members who were active in a 28-day period, and inactive members get a prorated credit, per the FAQ on its pricing page.

Here's what that looks like for a real budget. Say Lauren runs marketing at a 40-person software company in Austin, and she's been asked to price both. At list price, paid yearly, Slack Pro is $3,480 a year for 40 people and Business+ is $7,200. Teams Essentials is $1,920, and Business Basic is $3,360 with email and Office apps included. Her company already pays for Google Workspace, so Business Basic would mostly duplicate what they have. That's why, for her, the honest comparison is $3,480 for Slack Pro against $1,920 for Teams Essentials, and the question becomes whether Slack's apps and channels are worth about $1,560 a year to a team that lives in Jira and Salesforce. For most 40-person software companies I'd say yes.

Meetings: Slack huddles vs Teams meetings

This is the clearest difference between the two.

Slack huddles are quick calls inside a channel or DM. On paid plans, Slack's huddles guide says a huddle can have up to 50 people, with up to 25 on video at once and two people sharing their screen at a time. Each huddle gets a canvas for notes, and paid plans can have AI take the notes for you.

Teams is built for scheduled meetings. Every business plan on Microsoft's comparison lists meetings of up to 30 hours with up to 300 people, plus recordings and transcripts. Live captions cover English on Teams Essentials and more than 30 languages on the Microsoft 365 plans.

Picture Marcus, an operations manager whose team is split between New York, Denver and San Francisco. His weekly ops review runs at 11 a.m. ET, which is 9 a.m. in Denver and 8 a.m. in San Francisco, with 40 people, a recording for whoever's on PTO, and captions. That's a Teams meeting. Now say three of his leads need five minutes to sort out a shipping delay. A Slack huddle is faster to start, and the conversation stays next to the thread it came from.

Working with people outside your company

If you work with clients, agencies or freelancers, check this part carefully, because the plan you choose decides it.

• Slack needs a paid plan for both options. Guests join your workspace, and Slack lets you add up to five single-channel guests for each paid active member. Slack Connect shares a channel with other companies' own Slack workspaces, up to 250 organizations on paid plans.
• Teams offers guest access, which gives an outside person access to teams, channels, chats, meetings and files with any business or personal email address. Microsoft also offers shared channels, and external access for chatting, calling and meeting with people at other Microsoft 365 organizations.

Teams guest access is managed through your Microsoft 365 admin settings, so it's worth asking whoever runs your IT what's switched on before you promise a client a seat.

This is where agency life gets messy. Say Greg is an account manager at a Chicago ad agency with a dozen clients. Half of them use Slack, so a Slack Connect channel per client keeps each conversation in Greg's own sidebar. A bank client runs on Microsoft 365 and invites him in as a guest on Teams instead. Greg will end up in both apps no matter what his agency picks. My advice for anyone in his seat: let the client choose the tool, and keep one running doc per client so the decisions don't get split between two apps.

Integrations: Slack vs Teams apps

Slack's pricing page says its App Directory has over 2,600 apps, and paid plans remove the 10-app cap. If your team uses Jira, Google Drive, Salesforce and a dozen other tools from different companies, Slack is usually the easier place to bring them together.

Teams' strength is how close it sits to the rest of Microsoft 365. Microsoft lists over 250 integrated business apps on its Business plans, but the bigger draw is that your Outlook calendar, SharePoint files and Word documents are already there. If most of your work happens in those, that matters more than the size of an app store.

AI in Slack vs Teams: what each plan includes

Both companies have changed how they package AI, so it's worth checking the exact plan rather than the marketing.

Slack AI

Slack folded its old AI add-on into its plans in 2025. According to Slack's announcement, conversation and thread summaries and huddle notes are on every paid plan. AI search, daily recaps, translations and file summaries need Business+ or Enterprise+, and enterprise search is Enterprise+ only. Slackbot, Slack's personal AI agent, comes with ongoing access on Business+ and Enterprise+ (with plan limits), while its pricing page says Free and Pro users get a limited trial.

Copilot in Microsoft Teams

Microsoft splits it in two. Copilot Chat, an AI chat with web results and writing help, comes at no extra cost with eligible Microsoft 365 subscriptions, and Business Basic lists it. Microsoft 365 Copilot, the version that works with your own meetings, chats and files in Teams, is built into Business Standard with Copilot at $23.50, or is an add-on for other eligible plans. Microsoft lists the Copilot Business add-on at $21 per user per month paid yearly, with a promotional price through December 31, 2026. Microsoft also notes that some advanced AI features are billed by usage on top of the license.

My advice is to write down the one AI job you actually want, like a summary of a meeting you missed, and check that exact feature on the plan you're about to buy. If Marcus's main wish is a recap of the 11 a.m. ops review for his San Francisco leads, that's Microsoft 365 Copilot territory, not Copilot Chat, and he should budget for it.

Security and compliance: what each plan includes

Comparisons often skip this part, yet it's what your IT lead, or your biggest customer's security questionnaire, will ask about first. Both products encrypt your data. The differences are in who controls sign-in, how long data is kept, and what you can export or put on legal hold.

On Slack, the line to know is Business+. Slack's plans page puts data residency and exports of all messages there, and Slack's export guide says exports that include private channels and DMs have to be applied for and approved by the Workspace Primary Owner. Audit logs, native data loss prevention, legal holds and HIPAA compliance are Enterprise+ only.

On Microsoft, the line is Business Premium. Microsoft's business plans page lists Business Premium with Copilot at $32 per user per month, paid yearly, and it's the plan with Intune for managing company laptops and phones, Defender for Business against ransomware and malware, and Purview data loss prevention for email and files. Basic and Standard get spam and malware filtering and time-of-click protection for links.

If you're in healthcare, this matters more than anything else in the article. Microsoft says its HIPAA Business Associate Agreement is available by default to covered entities and business associates through its data protection addendum, and it lists Microsoft Teams among the in-scope services. On Slack, HIPAA compliance is an Enterprise+ feature. Picture a small physical therapy practice in Columbus that wants staff to discuss patient scheduling in chat: Microsoft is usually the simpler path, because the agreement isn't tied to a top-tier plan. Either way, a signed agreement doesn't make you compliant on its own; how you use the tool still matters.

Which should you choose?

• You already pay for Microsoft 365. Start with Teams. You have it, it's tied into your email and files, and adding Slack means a second bill.
• You use Google Workspace and lots of separate tools. Slack fits more naturally. Pro covers most small teams.
• You meet more than you message. Teams. The 300-person, 30-hour meetings are hard to beat at $4.
• You work with lots of outside partners who also use Slack. Slack Connect makes shared channels with them easy.
• You handle health data or answer security questionnaires. Price Microsoft 365 Business Premium against Slack Enterprise+ before anything else, because that's where the compliance features live.
• You're a handful of people with no budget. Teams free for calls, Slack Free for chat, and accept that Slack forgets after 90 days.

Switching from Slack to Teams, or Teams to Slack

Most teams don't pick from a blank page. They're on one and wondering about the other, usually because finance noticed two bills. Here's what a move really involves, so you can decide whether it's worth it.

Moving from Slack to Teams

Microsoft's Slack-to-Teams migration guide is candid about the limits. What you can take depends on your Slack plan. Slack's export guide says public channel messages and file links can be exported on any plan, while private channels and DMs need Business+ and an approved request. Microsoft says Teams doesn't currently support importing direct messages, and points you to partner tools for that. Files usually come across as links you then copy into the matching Teams channel.

Microsoft's other piece of advice is structural. A Slack workspace usually maps to a team in Teams, and each Slack channel becomes a channel inside it, so you'll want to group your busiest channels before you start. Its guide also suggests removing Slack access on an agreed date as each person joins Teams, so you aren't exporting the same history twice.

Moving from Teams to Slack

Slack's own Teams-to-Slack migration guide lays out a phased plan for Free, Pro and Business+ teams: audit how Teams is used, set channels you don't need to read-only, and rebuild your most important workflows in Slack first. Slack says a technical architect can move message history as part of a professional services engagement, and it sends enterprise customers to its sales team. If your company keeps Outlook and Teams meetings, Slack's Microsoft Teams Calls app lets people start and join Teams calls from inside Slack.

Announce the switch so people actually follow it

Whichever way you go, the announcement decides how messy the next month is. Here's the kind of note I see far too often, and the version I'd send instead. Say Marcus is moving his team from Slack to Teams because the company already pays for Microsoft 365.

Subject: Moving to Teams

Hi all, we're switching to Microsoft Teams next month. Please download it and start using it. Thanks!

Subject: We move to Teams on Monday, November 2 (last day in Slack: Friday, November 13)

Hi team,

Starting Monday, November 2, all ops conversations move to Microsoft Teams. You already have it through your Microsoft 365 login.

What moves: our #ops, #shipping and #vendors channels become channels in the Operations team. Shared files are being copied over this week.

What doesn't: Slack DMs won't come across. If a DM has something you need, save it or post it in the right Teams channel before November 13.

After Friday, November 13, please don't post in Slack. You can still search it until December 31.

Questions go in the "Teams help" channel. I'm holding office hours on Teams on Tuesday, November 3, at 1 p.m. ET (11 a.m. MT, 10 a.m. PT).

Thanks,
Marcus

The second version answers the four questions people actually have: when, what moves, what doesn't, and where to ask. It also puts the key dates in the subject line, because that's what people search for a week later.

How to test Teams and Slack before you switch

Both have free versions or trials, so I'd test with one real piece of work rather than a feature checklist:

1. Pick one small project with a clear end, and invite the people who'd actually use the tool.
2. Set up two or three clearly named channels for it.
3. Share a working document and make one decision about it in writing.
4. Run one meeting and write down the next step where everyone can see it.
5. Invite one outside person the way you would for real.
6. A week later, ask someone who missed the conversation to find that decision without help.

That last step tells you more than anything else. The tool where people can still find yesterday's decision is the one that'll work for your team. If you go with Slack, our guide to scheduling Slack messages helps with time zones. If it's Teams, here's how to set an out of office in Teams.