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Data Transfer Pricing

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This course explores the cost metrics associated with the Amazon Relational Database Service, known as RDS. Minimizing cloud spend is always a priority when architecting and designing your cloud solutions, and care should be taken to understand where your costs come from and the steps you can take to reduce them.

This course looks at each of the components associated with RDS that incur a cost and how those costs are broken down. It looks at on-demand instances, reserved instances, database storage & I/Os, backup storage, backtrack storage, snapshot export, and data transfer.

If you have any feedback relating to this course, please feel free to contact us at support@cloudacademy.com.

Learning Objectives

  • Understand the different database instance purchasing options and payment plans
  • Learn about primary storage and I/O pricing options
  • Explore the costs associated with backup storage and backtrack storage
  • Learn about the pricing for snapshot exports and data transfers

Intended Audience

This course is intended for anyone responsible for designing, operating, and optimizing AWS Database solutions. It would also be advantageous for individuals planning to take the AWS Certified Database - Specialty exam.


To get the most from this course, you should have a basic understanding of the AWS global infrastructure. It would be beneficial, but not essential, to have a basic awareness of the database engines covered in this course, i.e. Amazon Aurora, MySQL, PostgreSQL, MariaDB, Oracle, and SQL Server.


When we talk about data transfer there are a number of different data paths where you might be charged for transferring data IN to and OUT of your RDS database depending on the source and destination, for example:

  • Data transferred IN to your RDS database from the internet
  • Data transferred OUT from your RDS database to the internet
  • Data transferred OUT to Amazon CloudFront
  • Data transferred OUT to AWS Regions
  • Data transferred OUT to EC2 instances in the same availability zone
  • Data transferred between availability zones for multi-az replication
  • Data transferred between an EC2 instance and an RDS instance in different availability zones of the same region
  • Data transferred when a snapshot copy is transferred to a different region

Across the different DB engines, there is consistency when it comes to data transfer costs, so let’s take a look at each of the price points individually.  In the following examples, I will be taking the pricing from the MySQL DB engine.

Firstly, let me show you under which circumstances you will NOT be charged for data transfer and so it completely free, this includes:

  • Any data that is transferred IN to your RDS database from the internet
  • Any Data that is transferred OUT to Amazon CloudFront
  • Any data that is transferred OUT to EC2 instances in the same availability zone
  • Data transferred between availability zones for multi-az replication - For those who might be new to Multi-AZ, it simply means Multi-Availability Zone, which is a feature that is used to help with resiliency and business continuity. When Multi-AZ is configured, a secondary RDS instance, known as a replica, is deployed within a different availability zone within the same region as the primary instance. That's its single and only purpose, to provide a failover option for a primary RDS instance.  As a result, there is a requirement for data replication between the primary and the secondary.

Data transferred OUT from your RDS database to the internet: This element of data transfer is very dependent on how much data you transfer per month and is charged per GB.  As a result, the resulting pricing is reflected as a tiered structure as you can see.

The first GB each month is free, and then as the amount of data transferred increases in Terabytes, the amount charged in GB decreases.  The more you transfer out to the internet, the cheaper per GB your data transfer becomes.

If data is transferred from RDS out to another region, then you will incur a small charge per GB, and as it stands at the time of writing this course, this is a flat fee of $0.02 per GB for ANY region that the data is transferred to.  

In this instance, charges will apply for Amazon EC2 regional data transfer both sides of the transfer and is charged at $0.01/GB in each direction.

As explained earlier, Snapshots in RDS are your backups of your database tables and instances, and these snapshots can be both exported out of Amazon RDS and copied to another region.  These Cross-region snapshots are a great way to help you implement a disaster recovery strategy across your RDS database infrastructure.

When copying your snapshots across regions you are just charged for the amount of data transferred based on the size of the snapshot, based on $0.02 per GB.

About the Author
Stuart Scott
AWS Content Director
Learning Paths

Stuart has been working within the IT industry for two decades covering a huge range of topic areas and technologies, from data center and network infrastructure design, to cloud architecture and implementation.

To date, Stuart has created 90+ courses relating to Cloud reaching over 140,000 students, mostly within the AWS category and with a heavy focus on security and compliance.

Stuart is a member of the AWS Community Builders Program for his contributions towards AWS.

He is AWS certified and accredited in addition to being a published author covering topics across the AWS landscape.

In January 2016 Stuart was awarded ‘Expert of the Year Award 2015’ from Experts Exchange for his knowledge share within cloud services to the community.

Stuart enjoys writing about cloud technologies and you will find many of his articles within our blog pages.