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Panel rating · 6 judges · How to read the stars

Category median

Sovereignty: not determined

0–5 in half steps. 5 means the rubric's top anchor is met on the evidence.

by Salesforce, Inc. · slack.com

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Read this page as one judge. Each weighs the same scores by what they care about.

The Team Lead

Weighted verdict

Runs a distributed team and needs the tool people actually open. Wants threads that stay readable, search that finds last spring's decision, and channels that can be tidied without losing history. Unmoved by feature lists that do not survive a busy Tuesday.

Same scores as the panel view — this lens weights them the way this judge cares.

Scored by The Team Lead

Channels, threads & search

How this is scored

The daily surface: channel model, threading, mentions, files, and whether search can find a decision made eighteen months ago.

0 — Flat group chats with no threads; search covers recent messages only, and history is capped.

3 — Channels and direct messages with basic search, but threading is awkward or absent and file handling is a plain attachment list.

5 — Public and private channels, real threads, mentions and reactions, file sharing with previews, and full-text search across the whole history.

8 — Cross-organisation or guest channels with clear boundaries, message editing history, pinned and saved items, search with filters by channel, person and date, and a documented history limit or none at all.

10 — The archive is a working knowledge base: search that ranks well across years, threads that stay readable, channel lifecycle management (archive, rename, merge) without losing history, and export of a conversation in a form a human can read.

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The Team Lead

Channels, Slack Connect, file sharing and search across the company's entire stored knowledge are evidenced, and history is unlimited from Pro upward — the daily surface works. But nothing in the evidence speaks to threads staying readable, edit history, pinned items, filtered search, or archiving a channel without losing its history, so the 'archive as knowledge base' half of the scale is unevidenced. 1 2 2

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Encryption & access control

How this is scored

What is encrypted and against whom, plus who can reach which room. Judged on documented mechanism, since "encrypted" in this category usually means the vendor holds the keys.

0 — Transport encryption only, undocumented; no role model beyond admin, guests indistinguishable from members.

3 — TLS and encryption at rest with vendor-held keys, basic roles, and guest access that mostly works.

5 — The above plus configurable roles per channel, SSO, guest accounts with scoped visibility, and a clear statement of what the vendor can read.

8 — Optional end-to-end encryption for direct messages or private rooms with the trade-offs named, device verification, session management an admin can revoke, and documented key handling.

10 — End-to-end encryption as a first-class mode — documented or open cryptography, cross-device key management that ordinary users survive, identity verification, and the vendor stating plainly what it cannot decrypt.

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The Team Lead

Encryption at rest and in transit with vendor-held keys, SSO down to the free tier, 2FA, and an Enterprise Key Management add-on for customer-held keys — solid but conventional. No end-to-end encryption anywhere, no device verification or admin-revocable session management documented, and no plain statement of what Slack itself can read beyond promises about LLM training. 2 1 2

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Retention, discovery & co-determination

How this is scored

The archive as a legal object: retention policies, export for discovery, audit, and the monitoring features a works council will ask to have switched off.

0 — No retention policy, no export beyond a manual copy, no audit log, and presence or activity analytics that cannot be disabled.

3 — Manual export of some data and a global history limit, but no per-channel retention, no audit log and no admin control over analytics.

5 — Configurable retention per channel or workspace, admin export in a documented format, an audit log of administrative actions, and status or presence that a user can control.

8 — Legal-hold and eDiscovery export including edits and deletions, retention executed per policy and evidenced, full admin audit trail, and activity analytics switchable off organisation-wide.

10 — Built to pass a works agreement and a subpoena on the same day: granular retention with documented deletion, discovery export a lawyer can use, complete audit, and no individual-level productivity scoring anywhere in the product.

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The Team Lead

Retention configurable at workspace and channel level (plan-dependent), plus legal hold, audit logs, DLP and information barriers on the pricing page — the legal object is at least named. Missing: eDiscovery export including edits and deletions, evidenced policy execution, and any word on whether activity analytics can be switched off organisation-wide, which is exactly what a works council asks first. 3 2

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Deployment & data custody

How this is scored

Whether the customer can hold their own archive: self-hosting, private cloud, open source, federation, and what an exit actually looks like.

0 — Cloud-only, proprietary, with export limited to a partial archive.

3 — Cloud-only, but with a documented full export in an open-ish format.

5 — A private-cloud or dedicated-instance option, or a self-hosted edition that lags the cloud significantly; full export documented.

8 — A genuine self-hosted edition close to feature parity, or open-source core with a documented upgrade path, plus complete export including files and metadata.

10 — Custody is the customer's: open-source or source-available server, self-hosting supported as a first-class deployment, open protocol or federation, and a migration path in and out that the vendor documents rather than resists.

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The Team Lead

Cloud-only from a proprietary San Francisco vendor: no self-hosting, no open-source core, no documented export format anywhere in the evidence. The only custody-adjacent facts are Germany hosting from Business+ and Slack hosting its own LLMs in its own AWS private cloud — neither puts my archive in my hands. 2 2

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Integrations & extensibility

How this is scored

Bots, webhooks, app framework, identity — whether the chat becomes the place work is noticed, and whether that is buildable without a partner agreement.

0 — No API, no webhooks, no bots.

3 — Incoming webhooks and a handful of native integrations; no bot framework, no documented limits.

5 — Documented REST API, incoming and outgoing webhooks, slash commands, a bot account model, and SSO.

8 — A proper app framework with interactive components, event subscriptions with retries, SCIM provisioning, documented rate limits and a sandbox.

10 — A platform: versioned API with a deprecation policy, an app directory or plugin system with permissions a customer can audit, and integrations the vendor maintains rather than lists.

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The Team Lead

An average of 43 apps per team and 1.7M weekly active apps say the ecosystem is real, automations are buildable 'with a click or by code', third-party services are controllable per workspace, and SCIM provisioning exists. 1 2 3

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European sovereignty

How this is scored

Where the archive and its metadata live, who the contracting entity is, which subprocessors touch it. Independently sourced by the sovereignty pipeline; scored here as this buyer weighs it.

0 — Non-EU vendor and contracting entity, hosting unstated or non-EU, subprocessors unnamed.

3 — EU data residency offered for message content while metadata, search indexes or support tooling remain non-EU, or the contracting entity sits outside the EU.

5 — EU hosting as standard and an EU contracting entity, but parts of the chain — notifications, AI features, analytics — are non-EU without an explained safeguard.

8 — EU hosting on named infrastructure, EU contracting entity, full subprocessor list published, any non-EU processing named with its legal basis.

10 — Sovereign end to end and evidenced: vendor, entity, hosting and every subprocessor European, certification published, and a self-hosted option that removes the question.

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The Team Lead

Salesforce, Inc. of San Francisco is the vendor and contracting entity, Germany data residency exists but only from Business+ upward, and no subprocessor list is published — the classic 'EU residency offered while the entity sits outside the EU' position. The LLM stack staying inside Slack's AWS private cloud is a nice touch but it's still Slack's cloud, not mine. 2 2

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Pricing transparency

How this is scored

Whether a buyer can compute the annual invoice for their headcount — including the retention, compliance and guest features they actually need — from public pages alone.

0 — No public prices at all; every tier is a sales conversation.

3 — A per-user headline exists, but the tier where retention control, SSO or compliance export begins is unstated.

5 — Per-user prices public with billing period stated, but at least one commonly needed capability (unlimited history, SSO, eDiscovery) sits in an unpriced enterprise tier.

8 — Every tier priced publicly with per-user maths, history and storage limits, feature boundaries, minimum term and VAT treatment stated; self-hosted licensing priced too where offered.

10 — Complete price computability: annual invoice derivable for a given headcount and deployment choice, including guest users, storage and any per-instance licence.

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The Team Lead

Tier boundaries are unusually legible — SSO down to the free plan, unlimited history from Pro, Germany residency from Business+, DLP on every tier — and VAT-compliant invoices are a product feature. But no per-user figure is captured in this evidence and the compliance tier (legal hold, SCIM, audit) sits in Enterprise+ without a stated price, so I cannot compute my annual invoice from these pages alone. 2 2

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European sovereignty — proven facts

0 of 4 dimensions proven

Built only from facts shown on the vendor's own pages. A dimension we could not prove is left open, not scored as zero.

Ownership Not determined ⚠ unverified — uncited Report an error
Data residency Not determined ⚠ unverified — uncited Report an error
Subprocessors Not determined ⚠ unverified — uncited Report an error

Where this could be wrong

What we left out

A claim that does not survive our checks costs us the claim, not the page. This is what was taken off this one.

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Sources (12)

The pages every claim on this page was read from — each one checked, dated, and kept verifiable.

  1. 1 Vendor homepage slack.com Checked 15 Sep 2026 Details →
  2. 2 Pricing slack.com Checked 15 Sep 2026 +1 earlier capture: 15 Sep 2026 Details →
  3. 3 Privacy policy slack.com Checked 15 Sep 2026 Details →
  4. 4 Legal notice slack.com Checked 21 Sep 2026 Details →
  5. 5 Channels, threads & search — found from sitemap slack.com Checked 1 Oct 2026 Details →
  6. 6 Channels, threads & search — found from sitemap slack.com Checked 1 Oct 2026 Details →
  7. 7 Encryption & access control — found from sitemap slack.com Checked 1 Oct 2026 Details →
  8. 8 Encryption & access control — found from sitemap slack.com Checked 1 Oct 2026 Details →
  9. 9 Retention, discovery & co-determination — found from sitemap slack.com Checked 1 Oct 2026 Details →
  10. 10 Retention, discovery & co-determination — found from sitemap slack.com Checked 1 Oct 2026 Details →
  11. 11 Integrations & extensibility — found from sitemap slack.com Checked 1 Oct 2026 Details →
  12. 12 Integrations & extensibility — found from sitemap slack.com Checked 1 Oct 2026 Details →