Notion vs Slack: who uses which
Customers, public proof and the companies that use both.
On usedby, 117 companies use Notion and 50 use Slack. 5 companies use both, including OpenAI, Vercel, and Prem AI. Notion leads among the Fintech & Payments companies on usedby that use either tool, Slack among the Artificial Intelligence companies.Latest check Nov 13, 2026: 103 of 167 public lines checked. Counts include every proof level, job-post signals included. A company on both tools counts at any proof level, and a job post on one side is marked as such.
Who uses Notion, Slack, or both
Every company with a public proof for at least one of the two tools.
112
listed for Notion only
5
companies use both
1 of them is listed through a job post on one side, the weakest proof.
45
listed for Slack only
On usedby, 112 companies are listed for Notion only, 45 are listed for Slack only and 5 use both, 1 of them through a job post on one side, out of the 162 companies listed for at least one. An absent listing does not prove non-use.
Where it lands
Recently publicly listed customers
Who uses both
Companies with a public line on both tools, at any proof level: the strongest proofs come first, and a job post is marked.
| Company | First public proof, Notion | First public proof, Slack |
|---|---|---|
 OpenAI | On or before Apr 2025 | — |
 Vercel | On or before Nov 2024 | — |
 Prem AI | On or before Nov 2026 | On or before Nov 2026 |
 Read AI | On or before Nov 2026 | On or before Nov 2026 |
 Notionjob post for Notion | Job post, Oct 2026 | — |
By industry
Which tool the companies on usedby use, by industry. Shares of the companies on usedby that use Notion, Slack or both: a share of the companies on usedby, not of the market.
Listed for Notion onlyBothListed for Slack only
More common with Notion
- Fintech & Payments18 of the 21 Fintech & Payments companies on usedby that use either tool use Notion.
- DevTools & Infrastructure9 of the 11 DevTools & Infrastructure companies on usedby that use either tool use Notion, 1 of them alongside Slack.
- Marketing Tech9 of the 11 Marketing Tech companies on usedby that use either tool use Notion.
More common with Slack
- Artificial Intelligence14 of the 21 Artificial Intelligence companies on usedby that use either tool use Slack, 3 of them alongside Notion.
Source: every usedby line, from confirmed proofs to job-post signals (the weakest proof level).
Side by side
Facts from our data and from each vendor's public pages. Each line says where it comes from.
Vendor facts checked: Notion, 5 of 6; Slack, 4 of 6. Missing facts remain unverified, not absent features.
NotionSlackWhat customers report
Results as the vendor or the customer published them, with the source and the date.
Notion
saving more than 30 hours a month and giving every rep consistent feedback
RoomPriceGenie
Vendor case study, notion.com, published Nov 3, 2026
The system saves over an hour of reporting prep each week.
OpenAI
Vendor case study, notion.com, published Apr 3, 2025
Slack
that would take someone more than an hour
Mural
Vendor case study, slack.com, captured Nov 12, 2026
saves me four to five hours each week
Isometric
Vendor case study, slack.com, captured Nov 12, 2026
Evidence for your decision: Notion
Source observations. Check the required plan and conditions before choosing.
Documented tasks
EqualsAutomate internal business workflows
With Custom Agents in Notion, the team now automates documentation updates, release approvals, and customer feedback triage—saving 24 hours a week.
ToyotaAutomate internal business workflows
With Notion, every post gets drafted and sent for approval in an easy-to-follow workflow that ends with a single click of the “approve” button that reduced approval timelines by 3x.
Choice criteria
Free trial or free plan: YesSourced observation
Plan: Unknown
Free $0 per seat / month For individuals to organize personal projects and life.
Integration: SlackRecheck required
Plan: Unknown
Slack Public API Free 80K Google Drive Public API Free 2.3 228K GitHub Public API Free 31K Notion AI Connector for MS Teams
Integration: Google DriveRecheck required
Plan: Unknown
Slack Public API Free 80K Google Drive Public API Free 2.3 228K GitHub Public API Free 31K Notion AI Connector for MS Teams
Integration: GitHubRecheck required
Plan: Unknown
Slack Public API Free 80K Google Drive Public API Free 2.3 228K GitHub Public API Free 31K Notion AI Connector for MS Teams
Pricing: $20Sourced observation
Plan: Business
Scope: per seat / month
Business Recommended $20 per seat / month For growing businesses to streamline teamwork.
Integration: SlackSourced observation
Plan: Unknown
Conditions: Product scope needs verification
Product: notion
Setup and limits: Named plan, contract entitlement, connector scopes, permissions, volume limits and regional eligibility remain unknown.; Documented only; not_tested. No authenticated vendor operation executed.; Named integration listing only; operation semantics and data direction are not established.
SlackPublic APIFree
Questions about Notion and Slack
Which is used more, Notion or Slack?
Notion has more customers on usedby: 117 against 50 for Slack. Notion leads among the Fintech & Payments companies on usedby that use either tool, Slack among the Artificial Intelligence companies.
Do companies use both Notion and Slack?
Yes. 5 companies use both on usedby, including OpenAI, Vercel, and Prem AI.
Who uses Notion?
117 companies on usedby, each with the public page that shows it. See who uses Notion.
Who uses Slack?
50 companies on usedby, each with the public page that shows it. See who uses Slack.
How does usedby count customers?
A company counts when a public page shows it: a vendor's customer page, a case study, a press release or a job post, most saved with a dated capture. Every line is a customer, at one of four proof levels: confirmed, declared by the company itself, observed or signal (a job post, the weakest). A company counts as using both tools when it has a line on each, at any level; the list shows the strongest proofs first and marks job posts.