# Perplexity — Upcoming retirement of older OpenAI models

- Company: Perplexity (perplexity.ai)
- Announced: 2026-09-25T14:34:21+00:00
- Category: deprecation
- Coverage: not counted
- Announcement: yes
- Group: announcements
- Source: https://docs.perplexity.ai/docs/resources/changelog#september-2026
- Record: https://forck.live/items/13876-upcoming-retirement-of-older-openai-models
- Subject: Sonar
- Models affected: openai/gpt-5.4, openai/gpt-5.4-mini, openai/gpt-5.4-nano, openai/gpt-5.2, openai/gpt-5.1, openai/gpt-5, openai/gpt-5-mini

Perplexity will retire several older OpenAI model IDs (openai/gpt-5.4, openai/gpt-5.4-mini, openai/gpt-5.4-nano, openai/gpt-5.2, openai/gpt-5.1, openai/gpt-5, openai/gpt-5-mini) from its Agent API and Router API on October 24, 2026. Users must update direct model selections and fallback chains before the cutoff; after that date the retired IDs will no longer be accepted or returned by model-list endpoints.

## Evidence

Verbatim from https://docs.perplexity.ai/docs/resources/changelog#september-2026:

> On October 24, 2026 at 00:00 UTC, the Agent API and Router API will retire these model IDs: openai/gpt-5.4 ... After the cutoff, the retired IDs will no longer be accepted or returned by model-list endpoints.

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Record: https://forck.live/items/13876-upcoming-retirement-of-older-openai-models
Catalogue: https://forck.live/llms.txt
Current issue: https://forck.live/feed.md