Azure Database Migration Service (DMS) pricing, 2026

The Azure-native database replication tool, and why it is free for most migrations. The free Standard tier, the Premium tier billed per provisioned vCore-hour, the 183-day Premium free window, and the cost that actually matters: the destination Azure SQL.

Azure Database Migration Service (DMS) is the Azure-native tool for migrating databases into Azure SQL Database, Azure SQL Managed Instance, and SQL Server on Azure VMs, as well as a range of open-source engines. Unlike AWS Database Migration Service, which bills for a provisioned replication instance from the first hour, Azure DMS gives away its Standard tier entirely and gives the Premium tier free for the first six months. This page is the 2026 cost reference for Azure DMS specifically and the decision rules for when the Premium tier is worth provisioning.

Pricing verification

The two-tier structure was checked against the Azure Database Migration Service pricing page in June 2026. The Standard tier (1, 2, and 4 vCore) is free and supports offline migrations only. The Premium tier supports offline and online (continuous) migrations and is billed on a per-provisioned-vCore-hour basis; a 4-vCore Premium service is free for the first 6 months (183 days) from the date the DMS service is created, after which hourly charges begin. Microsoft does not publish a single flat per-vCore-hour rate that holds across all regions; confirm the current figure for your region on the Azure pricing calculator. Verified June 2026.

The two-tier pricing model

Azure DMS has exactly two pricing tiers, and the split is about downtime tolerance, not database size. The Standard tier is free and does offline (one-time) migrations: the source is quiesced or taken offline for the cutover. The Premium tier is paid (after the free window) and adds online (continuous) replication, so the application keeps running on the source while change data flows to the target, and downtime is limited to the final cutover.

Azure Database Migration Service tiers (June 2026)

Tier	vCore options	Migration type	Price
Standard	1, 2, 4 vCore	Offline (one-time) only	Free
Premium	4 vCore (provisioned)	Offline and online (continuous)	Per vCore-hour; free for first 183 days

The free Standard tier covers a large share of real migrations. Any workload that can tolerate a maintenance window equal to the full-load duration (a few hours for most mid-sized databases) can migrate on the Standard tier at zero tool cost. The Premium tier only earns its keep when the source database cannot be taken offline for that long, which is the case for business-critical OLTP systems with tight availability requirements.

The tool is usually free

For the majority of Azure database migrations the DMS tool costs nothing. Offline migrations run free on the Standard tier, and online migrations run free on the Premium tier for the first 183 days, which comfortably exceeds the duration of almost every single migration project. Budget the DMS line at or near zero and put the modelling effort into the destination Azure SQL compute, which is the cost that actually runs.

Standard versus Premium: choosing the tier

The decision is driven by one variable: how long the source database can be offline during cutover. If a several-hour maintenance window is acceptable, the Standard tier migrates the database for free. If the workload needs near-zero-downtime cutover (continuous replication while the source stays live), the Premium tier is required. Because Premium is free for the first 183 days on a 4-vCore service, the practical cost of choosing Premium is also zero for any migration that finishes inside that window.

Azure DMS tier selection by downtime tolerance

Scenario	Tier	Tool cost	Notes
Database can be offline for the full-load window	Standard	Free	Most non-critical and reporting workloads
Near-zero-downtime cutover required	Premium	Free for 183 days	Business-critical OLTP; continuous replication
Migration runs longer than 183 days	Premium	Per vCore-hour after day 183	Rare; usually signals a stalled migration

The cost that actually matters: the target Azure SQL

The DMS tool is rarely the line that drives an Azure database migration budget. The dominant cost is the destination Azure SQL Database or Azure SQL Managed Instance compute, which begins billing the moment the target is provisioned and runs indefinitely afterwards. During the migration there is also a parallel-running window where both the source database and the target Azure SQL are live, doubling the database spend for the cutover period.

For heterogeneous migrations (for example Oracle or IBM Db2 to Azure SQL), the largest single cost is the schema-conversion remediation labour, the work of fixing objects that do not automatically convert from the source engine to the target. That labour is partner-led and typically runs into five or six figures per database, dwarfing the free DMS tool. The discipline for Azure DMS budgeting is to treat the tool as free and concentrate on the destination compute, the parallel-running window, and any conversion labour.

Azure DMS versus AWS DMS

The two clouds bill their database-migration tooling on different models. AWS DMS provisions a replication instance priced like EC2 (a standard dms.r5.large is about $0.176 per hour) plus storage, billed from the first hour of use. Azure DMS gives the Standard tier away for free and gives the Premium tier free for the first 183 days, then bills per provisioned vCore-hour. The net effect: for short offline migrations Azure is free where AWS still bills instance hours, and for long online replications the two converge once the Azure free window expires. In both clouds the tooling cost is a rounding error next to the destination database compute and any conversion labour.

Database-migration tooling, Azure DMS vs AWS DMS (June 2026)

Dimension	Azure DMS	AWS DMS
Free offline tier	Yes (Standard, 1/2/4 vCore)	No (instance billed from hour one)
Free online window	183 days (Premium 4 vCore)	No
Billing unit after free window	Per provisioned vCore-hour	Per replication-instance-hour + storage
Serverless / auto-scaling option	No (provisioned vCore)	Yes (DMS Serverless, per DCU-hour)
Dominant real cost	Target Azure SQL compute	Target RDS/Aurora compute

The generational note: classic and modern Azure DMS

Microsoft has been rolling a newer generation of Azure DMS into the broader Azure migration toolchain through 2025 and into 2026. The classic Azure DMS service described here, with its Standard and Premium tiers, remains the primary entry point for 2026 database migrations. The modern capabilities lean more directly on Azure-native managed services and are layered on for specific scenarios. For planning purposes the cost story is unchanged: the tool is free or near-free, and the destination Azure SQL compute is the cost that runs.

How to keep Azure DMS cost at zero

Use the free Standard tier wherever an offline cutover window is acceptable. Most reporting and non-critical workloads qualify.
For online migrations, finish inside the 183-day Premium free window. Almost every single migration does; a migration that overruns it usually signals a stalled project, not a tool cost.
Decommission the DMS service as soon as cutover completes. A Premium service left running past day 183 starts billing vCore-hours for no reason.
Model the destination Azure SQL tier carefully. That is the cost that runs indefinitely, not the migration tool.
Minimise the parallel-running window. Every extra day of running both source and target doubles the database spend for that day.
For heterogeneous migrations, scope the schema-conversion labour early. It is the largest line and it dwarfs the free tool.

Azure Database Migration Service is one of the few migration tools that is genuinely free for most projects: free for offline migrations on the Standard tier, and free for the first 183 days of online migration on the Premium tier. The cost discipline for Azure DMS is not about the tool at all; it is about the destination Azure SQL compute, the length of the parallel-running window, and the conversion labour for heterogeneous sources.

Q&A

Frequently asked

Q. What does Azure Database Migration Service cost?

A. Azure DMS has two tiers. The Standard tier (1, 2, and 4 vCore options) is free and supports offline, one-time migrations. The Premium tier supports online (continuous) migrations with minimal downtime and is billed per provisioned vCore-hour for the lifetime of the migration service. A 4-vCore Premium service is free for the first 6 months (183 days) from service creation, after which hourly charges begin. For most migrations the DMS tool itself is effectively free; the cost that matters is the destination Azure SQL compute.

Q. Is Azure DMS free?

A. The Standard tier is free for all three vCore sizes (1, 2, 4 vCore) and covers offline, one-time migrations. The Premium tier, which adds online continuous replication for near-zero-downtime cutovers, is also free for the first 183 days on a 4-vCore service from the date the DMS service is created. Beyond that window the Premium tier bills per provisioned vCore-hour. Because most database migrations complete well inside 183 days, the tool is free in practice for the majority of projects.

Q. What is the difference between the Standard and Premium tiers?

A. The Standard tier supports offline (one-time) migrations only: the source database is taken offline or quiesced for the duration of the cutover. It is free across 1, 2, and 4 vCore sizes. The Premium tier adds online (continuous) migration, where change data is replicated while the source stays live, so the cutover downtime is measured in minutes rather than the full-load duration. Premium is the tier for business-critical workloads that cannot tolerate a long offline window; it is billed per provisioned vCore-hour after the 183-day free period.

Q. How does Azure DMS pricing compare with AWS DMS?

A. The two services bill differently. AWS DMS charges for a provisioned replication instance (priced like an EC2 instance, for example dms.r5.large at about $0.176 per hour) plus storage, from the first hour. Azure DMS gives away the Standard tier entirely and gives the Premium tier free for the first 183 days, then bills per provisioned vCore-hour. For a short offline migration, Azure DMS Standard is free where AWS DMS still bills instance hours; for long online replications the gap narrows once the Azure 183-day window expires. In both clouds the tooling cost is small relative to the destination database compute and any schema-conversion labour.

Q. What is the real cost of an Azure database migration?

A. The DMS tool is rarely the line that matters. The dominant costs are the destination Azure SQL Database or Azure SQL Managed Instance compute (which starts billing the moment the target is provisioned and runs indefinitely), the parallel-running window where source and target both run during cutover, and any schema-conversion remediation for heterogeneous migrations (for example Oracle or Db2 to Azure SQL). Budget the DMS tool at or near zero and put the modelling effort into the target compute tier and the length of the parallel-running window.

Q. Does Azure DMS support online migrations with minimal downtime?

A. Yes, through the Premium tier. Premium performs an initial full load and then continuously replicates changes from the source until cutover, so the application downtime is limited to the final cutover step rather than the whole migration. The Standard tier does not do continuous replication; it is offline only. If a workload cannot tolerate a long offline window, the Premium tier (free for the first 183 days on 4 vCore) is the right choice.