Vercel Sandbox Goes Global: Four Regions, Failover on Pro

Vercel Sandbox now runs in four regions, and region selection is available on every plan.

The changelog, published 24 August 2026, lists iad1 (Washington, D.C.), sfo1 (San Francisco), cle1 (Cleveland) and cdg1 (Paris). iad1 remains the default, and Vercel says support for all its regions is "coming soon". For teams running agent code execution or sandboxed builds, the sandbox can now sit next to the data it touches.

What actually changed

Capability	Who gets it
Region selection (4 regions)	All plans
Failover regions	Pro and Enterprise only
Default region	iad1, unless you change it

Failover is the substantive addition: if the primary region is unavailable, new sandboxes start in the closest configured failover region. Vercel's stated reason for choosing a region at all is latency — put the sandbox close to "the databases, object storage, and other services your sandboxes access".

The snapshot rule is the real constraint

One line in the changelog decides most migration plans: snapshots stay in the region where they were created and can't be moved. To create or resume a sandbox from a snapshot, both must be in the same region. During failover Vercel handles this automatically by loading the snapshot across regions.

So a snapshot-heavy pipeline does not simply follow a region switch. Changing your default region leaves existing snapshots behind in the old one, and the automatic cross-region load is documented for failover — not as a general "snapshots work everywhere" guarantee. Plan a region change as a snapshot rebuild, not a settings toggle.

How to set it

Update your tooling first, then set the region at the project level or per sandbox:

pnpm install @vercel/sandbox@latest   # Sandbox SDK
pnpm install -g sandbox@latest        # Sandbox CLI
pnpm install -g vercel@latest         # Vercel CLI

vercel project update my-project --sandbox-region cdg1 --sandbox-failover-regions iad1,cle1

Project settings live under Settings > Sandboxes. The SDK inherits those defaults; override per call:

const sandbox = await Sandbox.create({
  region: "cdg1",
  failoverRegions: ["iad1", "cle1"],
});

The CLI equivalent is sandbox create --name my-sandbox --region cdg1 --failover-regions iad1,cle1.

Which region to pick

Analysis, not guidance from Vercel: the region list is short enough that the decision reduces to where your Postgres and object storage already live. EU-resident data pairs with cdg1; a US-East database keeps iad1 and costs you nothing to leave alone. Three US regions against one EU region also means a US team gets a genuine failover pair, while an EU-only workload currently has no second EU option to fail over into — worth checking before you promise a recovery target.

There is a broader reason to care where the sandbox runs. A survey of terminal agents posted to arXiv on 20 August 2026 (arXiv:2608.20485, 52 pages) argues that agent behaviour "is jointly shaped by the model, interface, harness, runtime, and environment", and that prevailing evaluations emphasise final outcomes while exposing process quality, recovery and governance unevenly. The authors call for explicit reporting of system and runtime conditions. Region is now part of that runtime record.

What to watch

Two open items: when "all Vercel regions" actually lands, and whether failover stays a Pro-and-Enterprise feature once the region list grows. Until then, log the region alongside every agent run — a sandbox that failed in cdg1 and a sandbox that failed in iad1 are not the same data point.