How can i use SNS publish to send a SMS message using a phone number in another account.

Hi, Please follow the detailed steps below::

1. Source Account Setup (Account owning the phone number)

# Verify phone number sharing status
aws pinpoint-sms-voice-v2 describe-phone-numbers --phone-number-id your-phone-id

# Enable sharing for the phone number
aws pinpoint-sms-voice-v2 update-phone-number \
    --phone-number-id your-phone-id \
    --sharing-status SHARED

# Add resource policy
aws pinpoint-sms-voice-v2 put-resource-policy \
    --resource-arn "arn:aws:sms-voice:region:source-account:phone-number/phone-id" \
    --policy '{
        "Version": "2012-10-17",
        "Statement": [{
            "Effect": "Allow",
            "Principal": {
                "AWS": "arn:aws:iam::destination-account:root"
            },
            "Action": [
                "sms-voice:SendTextMessage",
                "sms-voice:DescribePhoneNumbers"
            ],
            "Resource": "arn:aws:sms-voice:region:source-account:phone-number/phone-id"
        }]
    }'

2. Destination Account Setup

# Verify shared phone number is visible
aws pinpoint-sms-voice-v2 describe-phone-numbers --owner SHARED

# Create origination pool
aws pinpoint-sms-voice-v2 create-pool \
    --origination-identity "arn:aws:sms-voice:region:source-account:phone-number/phone-id" \
    --iso-country-code US \
    --message-type TRANSACTIONAL

# Configure SNS to use the pool
aws sns set-sms-attributes \
    --attributes "DefaultSMSType=Transactional,DefaultSenderID=your-pool-id"

# Test message sending
aws sns publish \
    --phone-number "+1234567890" \
    --message "Test message"

3. For Cognito Integration

# Update Cognito SMS configuration
aws cognito-idp update-user-pool \
    --user-pool-id your-pool-id \
    --sms-configuration '{
        "SnsCallerArn": "arn:aws:iam::account-id:role/your-sns-role",
        "ExternalId": "your-external-id"
    }'

For more details:

• SNS SMS Publishing
• Phone Number Sharing
• Cognito SMS Configuration

Hi,

First, check if the phone number can be shared. Then, enable sharing for that number. Finally, set up a resource policy to allow the destination account to use the phone number for sending text messages and viewing its details.

Setting up the Destination Account

Start by confirming that the shared phone number is visible. Next, create a pool for originating messages using the shared number. Then, configure SNS to use this pool. Lastly, test sending a message.

Integrating with Cognito

Update the Cognito user pool's SMS configuration with the appropriate SNS role and external ID.