# Klaviyo: Major incident: Issues with Campaign Sending and Scheduling

**Summary:** Klaviyo reported a major campaign scheduling and sending incident starting 2026-01-12 11:12 UTC, lasting 1 h 10 min and resolved at 2026-01-12 12:23 UTC. New campaigns and scheduled RAST campaigns could not send; previously scheduled non-RAST campaigns continued processing. A fix restored service and all delayed campaigns were replayed; no data loss was expected. _(machine-written, sol)_
- Kind: Major incident · Label: degradation (model (Jev))
- Changed: 2026-01-12 11:12 UTC · Detected: 2026-10-17 18:22 UTC
- [Source: https://stspg.io/b9f5ync21nrr](https://stspg.io/b9f5ync21nrr)
- [Company: Klaviyo](https://rewindex.com/company/klaviyo.md)
- Versions: before (none: first archived) → after incident\_version:249/xpd2q1gf4vg7@ce39cd416b18
- Change 1 of 1 for this incident

## What changed

**1. Added: Title**

```diff
+ Issues with Campaign Sending and Scheduling
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2026-01-12 11:12 UTC
```

**5. Added: Resolved time**

```diff
+ 2026-01-12 12:23 UTC
```

**6. Added: Affected components**

```diff
+ Email Sending, Email Sending - Campaign Email Sending, Mobile Push Sending, SMS Sending - SMS Sending - Other, Text Message Sending
```

**7. Added: Update** (investigating) · 2026-01-12 11:12 UTC

```diff
+ Beginning around 5am US Eastern time, we began observing delays in campaign scheduling and sending. New campaigns, and scheduled RAST (calculate Recipient at Send Times) campaigns, are unable to send. However non-RAST campaigns that were scheduled prior to 5am US Eastern Time are processing as usual. We do not expect data loss. We are actively working to resolve the incident and will provide updates as soon as possible.
```

**8. Added: Update** (identified) · 2026-01-12 11:51 UTC

```diff
+ As of 6:45am US Eastern, the issue has been identified and a fix implemented. Any new scheduled or sent campaigns should process, with slight delays. We are actively replaying any campaigns that were delayed.
```

**9. Added: Update** (monitoring) · 2026-01-12 12:05 UTC

```diff
+ A fix has been implemented and we are monitoring results. Campaign sending and scheduling is back to normal, and all delayed campaigns have been replayed.
```

**10. Added: Update** (resolved) · 2026-01-12 12:23 UTC

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

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-01-12 11:12 UTC | Major incident: Issues with Campaign Sending and Scheduling (this change) | degradation |

All Klaviyo changes: [timeline](https://rewindex.com/company/klaviyo/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._


---
Canonical: https://rewindex.com/change/if39b675c1a7c40 · Markdown: https://rewindex.com/change/if39b675c1a7c40.md · JSON: https://rewindex.com/api/v1/changes/if39b675c1a7c40 · Generated 2026-10-18T00:57:30.973Z