AWS S3: Error 301 Moved Permanently — When S3 Redirects Break Your Uploads
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A 301 Moved Permanently isn’t a failure — it’s a nudge from S3 reminding you that data lives in regions, not abstractions.
Problem
You upload a file to your S3 bucket using the AWS CLI or SDK, and instead of a success message, you get:
Error: 301 Moved Permanently
The request didn’t fail — but it didn’t succeed either. It loops, redirects, or drops silently. You double-check the bucket name, endpoint, even credentials — everything looks fine. So why is S3 telling you to move?
Clarifying the Issue
A 301 Moved Permanently error in S3 doesn’t mean your object has moved. It means your request was sent to the wrong regional endpoint.
Each S3 bucket belongs to a specific AWS region. If your request goes to the wrong region or to the global endpoint (s3.amazonaws.com), S3 responds with a 301 redirect, telling your client to retry in the correct region.
However, not all tools automatically follow that redirect. AWS CLI and SDKs handle it well, but older scripts and third-party tools often fail silently.
You’ll typically see this error when:
- A bucket is created in one region but accessed via the global endpoint.
- Terraform or SDK clients are hardcoded to
us-east-1. - Legacy URLs reference the pre-2019 global S3 namespace.
- Cross-region replication or automation jobs point to the wrong host.
S3 isn’t broken — it’s enforcing regional accuracy.
Why It Matters
A 301 redirect might seem harmless, but in automation pipelines and SDK-based applications, it can cause major slowdowns or outright failures. Every redirect means your data traveled to the wrong region first — only to bounce back across AWS’s network.
Imagine a CI/CD job uploading logs to s3.amazonaws.com/my-bucket, while the bucket lives in us-west-2. Each request crosses continents before being redirected. Some SDKs handle this automatically, but others don’t — resulting in wasted bandwidth and confusing failures.
The fix is simple: always target the right regional endpoint.
Key Terms
- Regional Endpoint: A region-specific S3 address (e.g.,
s3.us-west-2.amazonaws.com). Using it ensures that all requests stay within the correct AWS data center. - Global Endpoint: The legacy
s3.amazonaws.comaddress. It was once universal but now only works reliably for buckets inus-east-1. - 301 Redirect: An HTTP signal that tells the client to retry the request at a different location.
- Signature Version 4 (SigV4): AWS’s request authentication method that ties signatures to specific regions. Mismatched regions in SigV4 headers often cause 301 or 403 errors.
- DNS Resolution: The process that maps your bucket name to the correct AWS endpoint. Using outdated DNS records can also trigger redirects.
Steps at a Glance
- Identify your bucket’s home region.
- Verify your endpoint URL or region flag.
- Update scripts, SDKs, or Terraform configs.
- Ensure your SigV4 signing region matches the bucket.
- Test with regional endpoints.
- Eliminate global URLs from future automation.
Detailed Steps
Step 1 — Find Your Bucket’s Region
The first step is to confirm where your bucket actually resides, since S3 redirects any request sent to the wrong region.
aws s3api get-bucket-location --bucket your-bucket-name
You’ll see output like:
{"LocationConstraint": "us-west-2"}
That’s your bucket’s home region.
Step 2 — Check Your Endpoint
Next, make sure your CLI or SDK targets the right regional endpoint.
aws s3 cp file.txt s3://your-bucket-name --region us-west-2
Or explicitly set the endpoint URL:
aws s3 cp file.txt s3://your-bucket-name --endpoint-url https://s3.us-west-2.amazonaws.com
Step 3 — Update Configurations and Terraform Providers
Ensure your infrastructure code matches your bucket region.
Terraform example:
provider "aws" {
region = "us-west-2"
}
Avoid assuming us-east-1 as a default. Modern S3 buckets require region-specific endpoints for all operations.
Step 4 — Validate Signature Version 4 (SigV4)
Requests signed with the wrong region will fail authentication or trigger redirects.
Example error:
The authorization header is malformed; the region 'us-east-1' is wrong; expecting 'us-west-2'.
Make sure your signing region matches your bucket region exactly.
Step 5 — Test with Regional Endpoints
Verify that your requests hit the correct region directly.
curl -I https://s3.us-west-2.amazonaws.com/your-bucket-name
Look for a 200 OK — no redirects.
Step 6 — Eliminate Global URLs from Automation
Replace old global-style URLs with regional ones to prevent future drift.
https://s3.us-west-2.amazonaws.com/your-bucket-name
This change eliminates latency, ensures predictable routing, and future-proofs your automation scripts.
ProTip — Always Specify the --region Flag
Even if your AWS CLI has a default region, explicitly setting --region ensures consistency across environments. It locks down behavior, clarifies logs, and prevents region mismatch errors during maintenance or migration.
Conclusion
A 301 Moved Permanently isn’t a failure — it’s a nudge from S3 reminding you that data lives in regions, not abstractions.
S3 is saying: “You’re close, but not quite there — try the right endpoint.”
By targeting regional endpoints, verifying SigV4 regions, and avoiding legacy global URLs, you eliminate one of S3’s most common phantom errors.
No more wandering uploads, no more redirects — just clean, direct, regional precision.
Aaron Rose is a software engineer and technology writer at tech-reader.blog and the author of Think Like a Genius.
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