AWS CloudFormation
User Guide (API Version 2010-05-15)

Override Parameters on Stack Instances

In certain cases, you might want stack instances in certain regions or accounts to have different property values than those specified in the stack set itself. For example, you might want to specify a different value for a given parameter based on whether an account is used for development or production. For these situations, AWS CloudFormation allows you to override parameter values in stack instances by account and region. You can override template parameter values when you first create the stack instances, and you can override parameter values for existing the stack instances. You can only set parameters you've previously overridden in stack instances back to the values specified in the stack set.

Parameter value overrides apply to stack instances in the accounts and regions you select. During stack set updates, any parameter values overridden for a stack instance are not updated, but retain their overridden value.

You can only override parameter values that are specified in the stack set; to add or delete a parameter itself, you need to update the stack set template. If you add a parameter to a stack set template, then before you can override that parameter value in a stack instance you must first update all stack instances with the new parameter and value specified in the stack set. Once all stack instances have been updated with the new parameter, you can then override the parameter value in individual stack instances as desired.

To learn how to override stack set parameter values when you create stack instances, see Add Stacks to a Stack Set.

To override parameter values in stack instances by using the AWS Management Console

  1. Open the AWS CloudFormation console at

  2. At the top of the page, choose StackSets. On the StackSets home page, select the stack set that you created in Create a New Stack Set. In that walkthrough, we created a stack set named my-awsconfig-stackset.

  3. With the stack set selected, choose Manage stacks in StackSet from the Actions menu.

  4. Choose Override parameters for selected stacks, and then choose Next

  5. On the Set deployment options page, in the Specify accounts area, choose Update stacks in account.

  6. In the Account text box, paste some or all target account IDs that you used to create your stack set in Create a New Stack Set.

  7. In the Specify regions area, choose all regions (hold down Ctrl while selecting regions to select multiple regions), and then choose Add to add all stack set regions to the list.

  8. In the Deployment options area, leave the default value of 1 and By number for Maximum concurrent accounts, and change the value of Failure tolerance to 1. Be sure Failure tolerance is also set to By number. Choose Next.

  9. On the Set overrides page, in the Delivery Channel Configuration section, for the Snapshot delivery frequency parameter check Override existing value and then select 6hours. You are instructing AWS CloudFormation to override the Snapshot delivery frequency parameter value and use 6hours for all the stack instances for the specified accounts in the specified regions. Choose Next.


    To set any overridden parameters back to using the value specified in the stack set, select Revert all parameters to StackSet values. Doing so removes all overridden values once you update the stack instances.

  10. Click Next.

  11. On the Review page, review your choices. Note that the Snapshot delivery frequency parameter displays an override icon, indicating that its value has been overridden at the stack level.

    Choose Edit in the upper right corner of each section to go back and make any changes, if necessary. When you are ready to update your stacks with the overridden parameter, choose Update stacks.