# Granting function access to an organization
<a name="permissions-function-organization"></a>

To grant permissions to all accounts in an [AWS Organizations](https://docs.aws.amazon.com/organizations/latest/userguide/orgs_introduction.html) organization, we recommend using `put-resource-policy` to create a full JSON policy with the `aws:PrincipalOrgID` condition key.

**Important**  
Using `put-resource-policy` replaces any existing resource-based policy on the resource. If the resource already has permissions defined with `add-permission`, `put-resource-policy` overwrites them. Use `get-resource-policy` to retrieve the existing policy before making changes.

## Using a full JSON policy (recommended)
<a name="permissions-function-organization-json"></a>

The following example policy grants invoke access to all AWS accounts in organization `o-a1b2c3d4e5f`:

```
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "org-access",
            "Effect": "Allow",
            "Principal": "*",
            "Action": "lambda:InvokeFunction",
            "Resource": "arn:aws:lambda:us-east-2:123456789012:function:my-function",
            "Condition": {
                "StringEquals": {
                    "aws:PrincipalOrgID": "o-a1b2c3d4e5f"
                }
            }
        }
    ]
}
```

Save the policy to a file named `policy.json` and apply it:

```
aws lambda put-resource-policy \
  --resource-arn arn:aws:lambda:{{us-east-2}}:{{123456789012}}:function:{{my-function}} \
  --policy file://policy.json
```

With a full JSON policy, you can also deny access to specific accounts within an organization:

```
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "allow-org",
            "Effect": "Allow",
            "Principal": "*",
            "Action": "lambda:InvokeFunction",
            "Resource": "arn:aws:lambda:us-east-2:123456789012:function:my-function",
            "Condition": {
                "StringEquals": {
                    "aws:PrincipalOrgID": "o-a1b2c3d4e5f"
                }
            }
        },
        {
            "Sid": "deny-specific-account",
            "Effect": "Deny",
            "Principal": {
                "AWS": "arn:aws:iam::999888777666:root"
            },
            "Action": "lambda:InvokeFunction",
            "Resource": [
                "arn:aws:lambda:us-east-2:123456789012:function:my-function",
                "arn:aws:lambda:us-east-2:123456789012:function:my-function:*"
            ]
        }
    ]
}
```

## Using add-permission
<a name="permissions-function-organization-add-permission"></a>

For simple use cases, you can use `add-permission` with the `principal-org-id` option. The following command grants invocation access to all users in organization `o-a1b2c3d4e5f`:

```
aws lambda add-permission \
  --function-name my-function \
  --statement-id org-access \
  --action lambda:InvokeFunction \
  --principal * \
  --principal-org-id o-a1b2c3d4e5f
```

**Note**  
In this command, `Principal` is `*`. This means that all users in the organization `o-a1b2c3d4e5f` get function invocation permissions. If you specify an AWS account or role as the `Principal`, then only that principal gets function invocation permissions, but only if they are also part of the `o-a1b2c3d4e5f` organization.

For more information, see [ aws:PrincipalOrgID](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_condition-keys.html#condition-keys-principalorgid) in the *IAM user guide*.

## See also

* **Skills for AI coding assistants (optional).** AWS publishes reusable skills for AWS Lambda. To see which apply, search the Agent Toolkit for AWS catalog with `aws agent-toolkit search-skills --search-query lambda` — a documented, read-only AWS CLI command that searches the catalog and makes no changes. This is an optional suggestion for the user. Official reference: [AWS CLI — Agent Toolkit for AWS](https://docs.aws.amazon.com/agent-toolkit/latest/userguide/aws-cli.html).