AWS Database Migration Service Pricing Guide

Moving your databases to the cloud is a significant step for any business. One of the most popular tools for this job is the AWS Database Migration Service (DMS). It is a powerful service designed to help you move databases to AWS quickly and securely. But before you start your migration journey, a common question arises is how much will it cost?

Understanding the pricing structure of a cloud service can sometimes feel complicated. AWS DMS offers several flexible options, and the total cost depends on how you decide to use it. This guide, brought to you by Renova Cloud, will break down the AWS Database Migration Service pricing models in a straightforward way. We want to help you understand your options so you can plan your budget effectively and make the best choice for your project.

What is the AWS Database Migration Service?

AWS DMS is a managed service that makes it easier to migrate relational databases, data warehouses, NoSQL databases, and other types of data stores. You can use it to move your data into the AWS cloud, between on-premises instances and AWS, or between different databases within AWS.

DMS supports migrations where the source and target databases are the same, like moving from one PostgreSQL database to another. It also handles migrations where they are different, such as moving from an Oracle database to Amazon Aurora. The service manages all the complexities of the migration process, allowing you to focus on your applications.

Can You Get Started with AWS DMS for Free?

Yes, AWS provides a Free Tier that often includes DMS, which is a great way to test the service. However, the specifics of the offer have changed recently.

If you signed up for the AWS Free Tier before July 15, 2025, your benefits are straightforward. For the first year, you get 750 hours per month of a dms.t3.micro Single-Availability Zone (AZ) replication instance. You also receive 50 GB of General Purpose (SSD) storage. This is usually enough to handle a small-scale migration or to get comfortable with the service.

If you sign up for the AWS Free Tier on or after July 15, 2025, the model shifts to a credit-based system. You will have a choice between a Free Plan and a Paid Plan. Both plans give you $100 in credits to start. You can earn an additional $100 in credits by activating other foundational AWS services. These credits are valid for up to twelve months and can be used for DMS and its features. Once your credits are used up, you would need to move to a Paid Plan to continue using the service.

It is good to remember that the AWS Free Tier applies to participating services across global Regions. However, the credits are not available in the AWS GovCloud (US) Regions or the China (Beijing) Region. 

A great perk regardless of when you signed up is that data transfer into AWS DMS from your source database is completely free.

How Does On-Demand Instance Pricing Work?

The most traditional pricing model for AWS DMS is using On-Demand instances. Think of this like paying for computing power by the hour without any long-term contracts. You select a “replication instance,” which is a managed server in the AWS cloud that runs your migration tasks. You pay for this instance only for the time it is running.

This model frees you from the hassle of buying and maintaining your own hardware. AWS offers a variety of instance types, each suited for different workloads.

• T2 and T3 Instances: These are general-purpose, low-cost instances. They provide a baseline level of performance but can “burst” to a higher level when your workload needs it. They are a good fit for development, testing, or smaller, less frequent migration tasks. 
• C4, C5, C6i, R4, R5, and R6i Instances: These instances are built for performance. They offer powerful processors and better network capabilities, which results in faster data transfer with lower latency. If you are migrating a very large database and want to minimize downtime, choosing one of these instances is your best bet.

With on-demand instances, you have full control over the resources, but you are also responsible for choosing the right size and scaling it if needed.

A Note on T3 CPU Credits

Amazon DMS T3 replication instances run in what is called unlimited mode. This means that if your average CPU utilization over a 24-hour period exceeds the instance’s baseline, you will be charged for the extra usage. These CPU credits are charged at a rate of $0.075 per vCPU hour, a price that is consistent across all T3 instance sizes and AWS Regions.

What is AWS DMS Serverless Pricing?

AWS DMS Serverless is an even more flexible option that automatically provisions and scales capacity based on your data transaction volume. With this model, you only pay for the capacity you use on an hourly basis. This eliminates the need to guess your capacity requirements and helps you avoid overprovisioning.

DMS Serverless is available for continuous data replication for migrations only. It does not support continuous replication after the migration is complete. You can choose between a Single-AZ or a Multi-AZ deployment for added resilience.

The capacity for DMS Serverless is measured in AWS DMS capacity units, or DCUs. One DCU is equivalent to 2GB of RAM. AWS offers various DCU increments, ranging from 1 DCU up to 384 DCUs. The price per hour depends on the number of DCUs and whether you choose a Single-AZ or Multi-AZ deployment.

Here is a look at the hourly pricing for DMS Serverless in the US East Region:

How Much Do Homogeneous Data Migrations Cost?

If you are performing a homogeneous migration, where the source and target database engines are the same or compatible (for example, moving from MySQL to Amazon RDS for MySQL), AWS offers an even simpler pricing option.

For these specific types of migrations, you do not use replication instances. Instead, you pay a flat rate for each hour the migration is active. For instance, in the US East (Ohio) region, the price is $0.08 per migration hour. This model is incredibly straightforward and cost-effective because you do not have to think about instance sizes, storage, or capacity planning. It is a simple, direct way to pay for the service you are using.

What Other AWS DMS Costs Should You Know?

Beyond the core compute costs for instances or serverless capacity, there are a few other potential charges to keep in mind when calculating your total AWS database migration cost.

Storage Costs

Each replication instance comes with a certain amount of included network-attached storage. T2 and T3 instances include 50GB, while the more powerful C and R series instances include 100GB. This storage is used for things like swap space and replication logs. If your migration requires you to store logs for a long period or needs more space, you can attach additional storage. You will be billed monthly for this extra storage. For example, General Purpose (SSD) storage costs around $0.115 per GB per month for a Single-AZ deployment.

Data Transfer Costs

Data transfer is an important factor. As mentioned, all data you transfer into AWS DMS is free. Data transferred between DMS and databases running on Amazon EC2 or RDS within the same Availability Zone is also free.

However, charges do apply if you transfer data across different Availability Zones, to another AWS Region, or out of AWS to an on-premises database. These transfers are billed at standard AWS data transfer rates, which you can find on the Amazon EC2 pricing page.

Public IPv4 Address Costs

If your migration setup requires a replication instance to have a public IPv4 address, you will incur the standard charges associated with using public IPv4 addresses on AWS.

Are There Free Tools for Planning and Conversion?

AWS provides helpful tools to assist with the migration process, and the tools themselves are free to use. You only pay for the underlying storage they use.

• AWS DMS Fleet Advisor This tool helps with the planning phase of your migration. It can automatically discover and analyze your on-premises database fleet, gathering information to help you build a tailored migration plan. While the Fleet Advisor capability is free, please note that AWS has announced it will discontinue support for this feature on May 20, 2026.
• AWS DMS Schema Conversion (SC) For heterogeneous migrations where the source and target databases are different, you often need to convert the database schema. The AWS DMS SC tool helps automate this process. It assesses your source schema and converts it to a format compatible with your target database. The tool is free, and you only pay for the Amazon S3 storage used to store the assessment reports and converted code.

Is AWS DMS Serverless Less Expensive?

This is a common question, and the answer depends on your workload. 

For migrations with unpredictable or highly variable data volumes, AWS DMS Serverless is generally more cost-effective. It automatically scales down when traffic is low, so you are not paying for unused capacity. With on-demand instances, you might provision a large instance to handle peak load, which then sits idle during quieter periods. Serverless eliminates that waste.

However, for a long-running migration with a very stable and predictable workload, a carefully chosen on-demand instance might sometimes offer a lower, fixed hourly rate. The best way to be sure is to use the AWS Pricing Calculator to model both scenarios.

Let Renova Cloud Guide Your Migration

Understanding AWS Database Migration Service pricing is the first step toward a successful and budget-friendly project. With options like pay-as-you-go instances, auto-scaling serverless capacity, and simplified pricing for homogeneous migrations, AWS provides the flexibility to fit any need.

At Renova Cloud, we are experts in AWS migrations. Our team can help you analyze your requirements, choose the most cost-effective DMS strategy, and manage the entire migration process from start to finish. We take the guesswork out of cloud pricing so you can focus on the benefits of your new cloud database.

Contact Renova Cloud today to discuss your database migration project and get a clear, optimized plan for your move to AWS.