What is an incident post-mortem?
Updated Nov 1, 2026
Definition
An incident post-mortem is a written review after an outage or incident that explains what happened, when, why, and what the team will change so it doesn't happen again. A blameless post-mortem focuses on systems and processes, not on who made a mistake.
What a post-mortem includes
- Summary and severity: what broke and who was affected.
- Timeline: what happened, minute by minute, from detection to recovery.
- Root cause: why it happened, and the factors that made it worse.
- What went well: so good practices are kept.
- Corrective actions: each with an owner and a date.
Why blameless
When people aren't afraid of blame, they share the full story, which is the only way to find the real root cause.
How Acta writes post-mortems
Acta's Incident post-mortem template turns the incident review meeting into a blameless post-mortem: summary, severity, impact, timeline, root cause, contributing factors and corrective actions with owners and dates.
Incident post-mortem templateFAQ
When should a post-mortem be written?
Within a few days of the incident, while the details are fresh. Many teams hold a review meeting first and write the document from it.
Is a post-mortem the same as a retrospective?
They're similar. A retrospective reviews a period of work, such as a sprint; a post-mortem reviews one incident.