Convert Access to SQL Server.

DBConvert & DBSync for Access and MSSQL is cross-database migration software for converting and synchronizing data between Microsoft Access (.MDB or .ACCDB) and SQL Server on-premises or in a cloud.

MS Access is a popular desktop database widely used in organizations. In time, most Access databases grow in size and complexity. When Access databases are becoming unstable and slow due to large amounts of data, it's time to consider migrating from Access to SQL Server.

MS Access vs SQL Server

Microsoft Access SQL Server
Microsoft advertises that MS Access has a size limit of 2 GB, but in fact, you will notice a performance and stability degradation above about 300 Mb. The SQL Server database usually performs much better than an Access database, especially with a large, terabyte-sized database.
Microsoft says the Access database cannot support more than 255 concurrent users. Actually, MS Access applications are NOT designed to support about 20 or more concurrent users on a LAN. By default, SQL Server allows a maximum of 32767 concurrent connections, the maximum number of users who can simultaneously log in to the SQL server instance. SQL Server processes queries much faster and efficiently by processing queries in parallel, using multiple native threads within a single process to handle user requests.
MS Access applications are NOT designed to be exposed to the Internet. There are some workarounds, such as Remote Desktop Connection, but these systems are always expensive to build and maintain. In most cases, it also shows poor performance. SQL Server can be easily configured for accessing over the Internet. Typically, the application interface connects to SQL Server databases over the Internet. Thus, employees, partners, and customers can exchange information and update it in real-time, wherever there is Internet access.
Overgrown Access databases can often crash and become corrupted. The built-in limitations of the MS Access applications itself, or sometimes the application's design quality, restrict its 24/7 operation. Let's say an operating system crash or power outage occurs. In this case, SQL Server can automatically restore the database to a consistent state in minutes and without the database administrator's intervention.

Migrate Access to SQL Server

So when it's time for your Access database to take it to the next level, you can upgrade to SQL Server, which supports larger amounts of data, more concurrent users, and more capacity. (on-premises or in the Azure cloud)

It would be an obvious choice to migrate overgrown Access databases to SQL Server as they are all produced by the same vendor.

However, for large data storage volumes with many clients, it would be reasonable to consider migrating a database to cloud-based solutions.

Why use DBConvert SQL Migration tools?

Our SQL migration tools are designed to convert and synchronize large and complex databases. Data can be migrated between local and remote databases as:

DBConvert software can automatically convert MS Access queries to SQL Server views. There is no need to know the differences between SQL dialects.

Sync Access to SQL Server

Trying to rewrite the entire system at once is the EXPENSIVE way to convert data from Access to SQL Server. In most cases, developing the target SQL Server requires more work than just creating a new database from scratch. The right way is a phased approach. In the early stages, legacy Access databases are often maintained for some time, with updated data flowing into both Access databases and SQL Server databases.

DBSync for Access and SQL Server is designed to synchronize data between Access and SQL Server databases.

Insert, Update, and Drop synchronization types give a strong consistency between Source and Target databases.


Note #1 Make sure every Access table has an index and a primary key. SQL Server requires all tables to have at least one index, and the linked table must have a primary key if the table can be updated.

Note #2 Forms, reports, macros, and VBA modules are not converted.

Note #3 Please be patient. The migration process can take a long time, depending on the size of the database objects and the amount of data that needs to be transferred.

Supported databases:
  • Microsoft Access x86/x64
  • Microsoft SQL Server
  • Access queries → MS SQL Server views
  • Azure Database for SQL Server
  • Amazon RDS
  • Amazon Aurora
  • Google Cloud
  • SQL Dump
 DBConvert for Access & MSSQL

Version: 6.1.4

Release Date: Sept. 20, 2022

 DBSync for Access & MSSQL

Version: 4.1.6

Release Date: Oct. 25, 2022

Try All-in-one DB migration and Sync software.

DBConvert Studio

 Version: 3.4.4

Release Date: Sept. 16, 2023

Supported databases:

  • SQL Server
  • MySQL
  • MariaDB
  • Percona
  • Oracle
  • PostgreSQL
  • Access
  • FoxPro
  • SQLite
  • Interbase
  • Firebird
  • IBM DB2
  • MS Azure SQL
  • Amazon RDS
  • Amazon Aurora
  • Heroku Postgres
  • Google Cloud

Using Access to SQL Server conversion and synchronization tools.

When you start DBConvert or DBSync application in GUI mode it guides you through several steps to set up the database migration or synchronization:

1. Connect to Access source database.

If a source database requires you to log in, you can specify a user name/ password and host/ port parameters.

Connect to Access source database from DBConvert

2. Connect to SQL Server destination database.

Specifying parameters for destination database looks like the same as for source. Usually, it consists of defining connection settings and username/password pairs.

Connect to SQL Server target database from DBConvert

NOTE #1: Every DBConvert or DBSync tool has two different databases in its name. That means any specified database from a pair can be set up as a source or destination. Besides, the same type of database may be set up both as a source or destination.

As an example, here is the list of possible migration directions with on-premises databases:

  • Access to SQL Server
  • SQL Server to Access
  • Access to Access
  • SQL Server to SQL Server

NOTE #2: Don't be confused by the fact that connections to cloud databases like Amazon RDS, Google Cloud, and Heroku are not explicitly specified in the configuration of a source or destination in the DBConvert / DBSync interface. To connect to Cloud database instances, use the same settings as you do for traditional on-premises databases.

NOTE #3: Your connections to source and target databases stay active until you close DBConvert/ DBSync application or reopen new connections on "source" and "destination" steps.

Read more about the specific source/ destination configurations for different databases.

3. Configure database migration options.

At the next step, you can specify precisely which tables, fields, indices, views you want to transfer to the SQL Server destination database. Just check/ uncheck the box in front of each database object you want to convert.

Customize general database/ tables settings. Or set up a particular table , field, index individually when migrating data from Access to SQL Server.

Check out our articles about Configure database migration options. for detailed information.

The screenshot below sums up general features available in DBConvert software solutions.

4. Detection of potential database migration issues. Errors and Warnings

The database typically constrains certain relations on the data that cannot be violated. On the customization step, a smart error checker verifies all possible Data integrity and Referential integrity issues and highlights them, if any, before performing a migration.

By default, DBConvert tries to automatically map the database types of the source Access database to the closest equivalent of the target SQL Server database types. However, you can manually change the data types for the entire database globally using the "Global mapping" or individually for each field.

Check out Smart error checker. Errors and Warnings for more information.

5. Execution. The final stage of data migration from Access to SQL Server

Once you configure source and destination databases for migration in the previous steps, you can start the actual conversion or synchronization process.

Click the "Commit" button to start conversion. Also, here, you can monitor the migtation/ synchronization process.

Optionally save connection settings and configuration parameters into the session file to schedule the launching of sync or migration jobs regularly.

Execution step of DBConvert products

Read more about execution stage available options.

Command line mode

Previously saved sessions can be passed as parameters to Command-Line DBConvert Client. A session keeps Access source and SQL Server target database connection settings with other specified options.

Example: C:\Program Files\DBConvert\access2mssqlPro\access2mssqlPro_Cons.exe /Session:"Session_Name"

NOTE: First, you have to run the software in GUI mode to create a session file with initial parameters.

Built-in scheduler.

Our applications come with a built-in scheduler to run database migration and sync jobs at specified times. Just set the scheduled date and time to execute job sessions automatically.

Find more Information about built-in scheduler

DBConvert screenshot

Supported OS:


  • Access 2000 or higher. Both Access 32/64 versions are supported
  • Microsoft Visual C++ 2008 x86 Redistributable package
  • Necessary privileges to write into database on the target SQL Server (this requirement is optional as there is an option to overcome the restrictions using dump file)


Read information about reverse migration.