Migrating off labs-leanstral-1-5 — retirement date and replacement
Source last checked: 2026-09-30.
Mistral is retiring labs-leanstral-1-5 on 2026-09-30 — in 0 days. The provider has not named a replacement in its own documentation, so the migration target is your decision. This page is built from Mistral’s official deprecation notice and is rechecked weekly; the source link is below.
When is labs-leanstral-1-5 being deprecated?
| Model | Provider | Retires | Replacement |
|---|---|---|---|
| labs-leanstral-1-5 | Mistral | 2026-09-30 | — not named |
Source: Mistral deprecation notice · announced 2026-09-29
Test before switching
- Check the replacement's supported API endpoints and request parameters.
- Test your prompts, structured output, streaming and tool calls on staging.
- Compare quality, latency, pricing and rate limits on your workload.
- Keep a rollback path while the old model remains available.
Download retirement dates for your models.
What should I migrate labs-leanstral-1-5 to?
Mistral has not published a successor for this model. That makes the decision yours, and it is worth treating as an opportunity to compare providers rather than defaulting to whatever is nearest. Endpoint responsiveness is measurable; model quality claims mostly are not.
Measured latency of the Mistral API host
| Region | p50 TTFB | p95 | Uptime | Probes |
|---|---|---|---|---|
| Asia (Tokyo) | 314 ms | 394 ms | 100% | 287 |
| Europe (Germany) | 100 ms | 299 ms | 100% | 289 |
| South America (São Paulo) | 242 ms | 310 ms | 100% | 288 |
| US (Central) | 193 ms | 270 ms | 100% | 287 |
Edge latency to the provider’s API host over the last 24 hours, measured from 4 regions. This measures the endpoint, not the model: swapping models on the same host is not an inference benchmark or a promise about the replacement model. Compare edge latency →
What else retires on 2026-09-30?
| Model | Provider | Retires | Replacement |
|---|---|---|---|
| mistral-ocr-4-0 | Mistral | 2026-09-30 | OCR 4.1 |
Same shutdown date. If you call more than one of these, they are one migration, not several.
Other Mistral models being retired
| Model | Provider | Retires | Replacement |
|---|---|---|---|
| zai-glm-5-2 | Mistral | 2026-10-31 | Z.ai GLM 5.3 |
| labs-leanstral-2603 | Mistral | 2026-06-30 | Leanstral 1.5 |
| mistral-medium-2508 | Mistral | 2026-08-31 | Mistral Medium 3.5 |
| mistral-small-2506 | Mistral | 2026-07-31 | Mistral Small 4 |
| voxtral-mini-2507 | Mistral | 2026-05-31 | Voxtral Mini Transcribe 2 |
| devstral-2512 | Mistral | 2026-07-31 | Mistral Medium 3.5 |
| magistral-medium-2507 | Mistral | 2025-11-30 | Mistral Medium 3.5 |
| labs-mistral-small-creative | Mistral | 2026-04-30 | Ministral 3 8B |
How is this calendar maintained?
Entries are pulled from provider documentation by an automated weekly job and every one carries a link to its source. Nothing is inferred from blog posts or social media. When a provider changes a date, the change appears here after the next run and is visible in the changelog. The full calendar across all providers is on the deprecations page, and this provider’s own list is at Mistral deprecations.