How to configure multi-region function deployment on Vercel

intermediate 8 min read Updated 2026-04-20

Quick Answer

Configure multi-region function deployment on Vercel by adding region specifications to your vercel.json file and using the functions configuration property. You can specify different regions for individual functions or set a default region for all functions.

Full Vercel Review

Prerequisites

Active Vercel account with Pro or Enterprise plan
Existing Next.js or Node.js project with serverless functions
Basic understanding of serverless functions and regions
Git repository connected to Vercel

Step-by-Step Instructions

Create or update your vercel.json configuration file

In your project root, create a vercel.json file if it doesn't exist. This file will contain all your deployment configuration including region settings. Ensure the file is in your project's root directory alongside your package.json.

Use a JSON validator to check your vercel.json syntax before deployment to avoid configuration errors.

Configure default region for all functions

Add the functions property to your vercel.json with a default region setting:

{
  "functions": {
    "pages/api/**/*.js": {
      "regions": ["iad1", "fra1", "syd1"]
    }
  }
}

This configuration applies to all API routes matching the pattern.

Start with regions closest to your primary user base for better performance.

Set region-specific function configurations

Configure individual functions for specific regions by targeting exact file paths:

{
  "functions": {
    "pages/api/users.js": {
      "regions": ["iad1", "fra1"]
    },
    "pages/api/analytics.js": {
      "regions": ["syd1", "hnd1"]
    }
  }
}

Each function can have different regional deployments based on usage patterns.

Deploy user-facing functions to multiple regions while keeping admin functions in fewer regions to optimize costs.

Choose appropriate regions based on user location

Select regions strategically using Vercel's available options: iad1 (US East), sfo1 (US West), fra1 (Europe), hnd1 (Asia-Pacific), syd1 (Australia). Consider your analytics data to determine where most requests originate from.

Use 2-3 regions maximum per function to balance performance and cost-effectiveness.

Configure environment variables per region

Set region-specific environment variables through the Vercel Dashboard under Settings → Environment Variables. Use the Region dropdown to assign different values per region. This is useful for database connections or region-specific API endpoints.

Use consistent naming conventions like DATABASE_URL_US and DATABASE_URL_EU for clarity.

Deploy and verify multi-region configuration

Push your changes to trigger a deployment, or run vercel --prod locally. Check the deployment logs in the Vercel Dashboard to confirm functions are deployed to specified regions. The Functions tab will show regional distribution.

Use the Vercel CLI command 'vercel logs' to monitor function execution across different regions.

Test function performance across regions

Use tools like Vercel's built-in analytics or external services to test response times from different geographical locations. Access your deployed functions and monitor the Analytics tab in your Vercel Dashboard to see regional performance metrics.

Test during peak hours in different time zones to get realistic performance data.

Monitor and optimize regional deployment

Review function invocation data in the Vercel Dashboard Analytics section. Look for patterns in regional usage and adjust your vercel.json configuration accordingly. Remove underutilized regions to optimize costs while maintaining performance.

Set up monitoring alerts for function errors or high latency in specific regions.

Common Issues & Troubleshooting

Functions not deploying to specified regions

Verify your vercel.json syntax is correct and the file paths match your actual function locations. Check that you're on a Pro or Enterprise plan, as multi-region deployment isn't available on Hobby plans.

High latency despite multi-region setup

Check if you're using the correct region codes in your configuration. Ensure your database or external APIs are also geographically distributed, as functions may still need to connect to distant resources.

Environment variables not working in specific regions

Verify environment variables are set for each target region in the Vercel Dashboard. Use the vercel env ls command to check which variables are available in which regions.

Increased costs after multi-region deployment

Review your function usage analytics and remove regions with low traffic. Consider consolidating similar functions or using edge functions for simpler operations that don't require full regional deployment.

Prices mentioned in this guide are pulled from current plan data and may change. Always verify on the official Vercel website before purchasing.

Visit Vercel View Vercel Pricing

Related to Vercel

ReviewVercel Review PricingVercel Pricing AlternativesVercel Alternatives