# Applying Cost Allocation Tags

The **duplo-project** cost allocation tag must be activated after you enable IAM access to billing data. Use the same AWS user and account that you used to enable IAM access to activate cost allocation tags.

It may take 1-2 days for new cost allocation tags to propagate in AWS. After that, DuploCloud's billing features will be fully functional and you can use the tag as a filter in the AWS Billing Cost Explorer.

Cost allocation tags can only be used to filter cost data generated after they are added.

To apply and activate cost allocation tags, follow the steps in [this document](https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/activating-tags.html).

After you activate the tag successfully, you should see this screen:

![Successful activation of cost allocation tags.](/files/Q40R6D50NvQaO3rWZHAJ)


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# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.duplocloud.com/docs/automation-platform/overview/use-cases/cost-management/cost-allocation-tags.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.