Understanding EC2 to S3 Data Transfer Cost | A Comprehensive Guide

Elastic Compute Cloud (EC2) instances and Simple Storage Service (S3) are two of the most widely used AWS services. When transferring data between these services, one should consider the costs involved (both upfront and hidden).

Generally, the EC2 to S3 data transfer cost is virtually zero if they are in the same region. However, transferring data from one AWS region to another does add to the bills. This article contains in-depth information about such charges to help you make informed decisions for managing your AWS infrastructure efficiently.

How Much Does Data Transfer Between S3 and EC2 Cost?

When transferring data from EC2 to S3, there are several methods to consider, each with its own cost implications. Here’s a breakdown of the associated charges with each.

Data Transfer within the Same AWS Region

As long as the S3 bucket is in the same AWS region or availability zone as the EC2 instance, data transfer between the two is free. However, there might be some hidden costs if you do the following:

• Invoke data transfers through a public IP instead of a private IP.  
• Transfer data from EC2 to S3 across different availability zones.

We recommend establishing a private network to bridge your EC2 instances and S3 buckets with an AWS Direct Connect or VPN. Doing so will save you some additional costs.

Data Transfer from EC2 to S3 in a Different Region

You will incur data transfer costs when moving data between EC2 instances and S3 buckets in different AWS regions. Downloading files from another AWS region can cost you around $0.02/GB on average. However, this may change depending on your selected region.

Data Transfer to S3 using the S3 Transfer Acceleration

S3 Transfer Acceleration is an optional AWS service that allows faster uploads to S3. It leverages the CloudFront delivery network to save time during large transfers. However, it comes with additional costs on top of the regular pricing for transferring data. Here’s what to expect.

Data Transfer IN to Amazon S3 from the Internet	Cost per GB
Accelerated by AWS Edge Locations in the United States, Europe, and Japan	$0.04
Accelerated by all other AWS Edge Locations	$0.08

Frequently Asked Questions and Answers (FAQs)

What are EC2 transfer costs?

You’ll have to pay $0.01 per GB for both sending and receiving data when moving data between EC2 instances, containers, or network interfaces in the same area. This charge applies whether you use Public or Elastic IPv4 addresses.

How much does it cost to move data between S3 buckets?

Moving data between S3 buckets in the same AWS region does not cost any charges. Likewise, if you transfer data from an S3 bucket to other AWS services in the same region, you won’t have to pay anything.

How can I reduce EC2 to S3 data transfer costs across different AWS regions?

You may consider using AWS Direct Connect or VPN (Virtual Private Network) for private network connections to reduce the overall transfer cost. Optimizing your data can also prove useful.

Conclusion

And there you have it. To summarize things, data transfer from EC2 to S3 is free for the most part, except when you use a public or Elastic IP address (1c per GB). Also, not all data transfer within an availability zone is free, especially when you consider VPC peering. We hope that helps clear up your confusion. Thanks for reading.