# Vercel: Major incident: SAML Single Sign-On (SSO) errors

**Summary:** Vercel reported a major SAML Single Sign-On outage preventing SAML/SSO login and access to SSO-protected teams through the dashboard and CLI. It started at 2026-07-16 08:39 UTC and resolved at 2026-07-16 10:45 UTC, lasting 2 h 5 min. Vercel identified the root cause and implemented a fix but did not specify either. _(machine-written, sol)_
- Kind: Major incident · Label: outage (model (Jev))
- Changed: 2026-07-16 08:39 UTC · Detected: 2026-10-17 18:22 UTC
- [Source: https://stspg.io/yzqkkrl8lw0m](https://stspg.io/yzqkkrl8lw0m)
- [Company: Vercel](https://rewindex.com/company/vercel.md)
- Versions: before (none: first archived) → after incident\_version:215/nw8xv7ypn7y0@35ecd192a6b5
- Change 1 of 1 for this incident

## What changed

**1. Added: Title**

```diff
+ SAML Single Sign-On (SSO) errors
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2026-07-16 08:39 UTC
```

**5. Added: Resolved time**

```diff
+ 2026-07-16 10:45 UTC
```

**6. Added: Affected components**

```diff
+ SAML Single Sign-On
```

**7. Added: Update** (investigating) · 2026-07-16 08:39 UTC

```diff
+ We are investigating SAML Single Sign-On (SSO) errors, leading to inability to login using SAML/SSO or access SSO-protected teams through the Vercel dashboard and CLI.
```

**8. Added: Update** (monitoring) · 2026-07-16 10:23 UTC

```diff
+ The root cause of the SAML Single Sign-On (SSO) errors has been identified and a fix has been implemented. We are seeing error rates decrease. Users should be able to login with SAML/SSO or access their SSO-protected teams through the Vercel dashboard and CLI again. We are continuing to monitor.
```

**9. Added: Update** (resolved) · 2026-07-16 10:45 UTC

```diff
+ This incident has been resolved.
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-07-16 08:39 UTC | Major incident: SAML Single Sign-On (SSO) errors (this change) | outage |

All Vercel changes: [timeline](https://rewindex.com/company/vercel/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._


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Canonical: https://rewindex.com/change/ib4d04a7a427c06 · Markdown: https://rewindex.com/change/ib4d04a7a427c06.md · JSON: https://rewindex.com/api/v1/changes/ib4d04a7a427c06 · Generated 2026-10-18T03:33:47.511Z