Executive Summary
Vercel has announced the official end-of-life for its legacy `now.json` configuration file, with support being formally removed on March 31st, 2026. The company is instructing developers to migrate their existing projects by renaming the file to `vercel.json`. For more advanced, programmatic configurations, Vercel highlights `vercel.ts` as an alternative.
Key Takeaways
* Legacy File Deprecation: Support for the `now.json` configuration file is being officially removed.
* Deadline: The final date for this change is March 31st, 2026.
* Simple Migration Path: To migrate, developers only need to rename their existing `now.json` file to `vercel.json`; no content changes are required for a basic transition.
* Advanced Option: For programmatic project configuration, `vercel.ts` is the recommended alternative.
Strategic Importance
This move standardizes project configuration on the Vercel platform, reducing technical debt and simplifying the developer experience by fully transitioning away from legacy naming conventions.