Validate Production Readiness During a Release Upgrade by Using a Non-Preview Sandbox

During the transition from one Salesforce major release to another, sandboxes get upgraded on different timelines based on their release type. Preview sandboxes provide early access to new features and are upgraded approximately 6 weeks before production orgs, while non-preview sandboxes are upgraded as the major release upgrade completes. Between the completion of a major release upgrade and the start of the next release upgrade, we attempt to create preview sandboxes by default when you create or refresh a sandbox. Now, you can choose to create a non-preview sandbox during this window of time. Previously, you could create a non-preview sandbox during this time window only by contacting Salesforce Customer Support.

Where: This change applies to Lightning Experience in Developer, Developer Pro, Partial Copy, and Full sandboxes.

When: The ability to opt into a non-preview sandbox is available after the rollout of the Summer ’26 major release is complete.

Why: With a non-preview sandbox, you can continue testing changes in an environment that’s identical to your production org without potential issues from the next release upgrade.

How: Contact Salesforce Customer Support to enable this feature. After this feature is enabled, select Request Non-Preview to create or refresh a sandbox during a release transition.