# System messages webhook reference | Developer Documentation

<div id="bkmrk-system-messages-webh">## System messages webhook reference

<div><span>Updated: Oct 22, 2025</span></div><div>This reference describes trigger events and payload contents for the WhatsApp Business Account **messages** webhook for system messages.</div><div>Note that unlike other incoming messages webhooks, system **messages** webhooks don't include a `contacts` array.</div><div id="bkmrk-triggers"><div id="bkmrk-triggers-1"><div>### Triggers

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<span>A WhatsApp user changes their WhatsApp phone number.</span><div id="bkmrk-parameters"><div id="bkmrk-parameters-1"><div>### Parameters

</div></div></div><div><table><thead><tr><th><span>Placeholder </span></th><th><span>Description </span></th><th><span>Example value </span></th></tr></thead><tbody><tr><td><div><div>`<BUSINESS_DISPLAY_PHONE_NUMBER>`</div><div>*String*</div></div></td><td><div><div>Business display phone number.</div></div></td><td><div><div>`15550783881`</div></div></td></tr><tr><td><div><div>`<BUSINESS_PHONE_NUMBER_ID>`</div><div>*String*</div></div></td><td><div><div>Business phone number ID.</div></div></td><td><div><div>`106540352242922`</div></div></td></tr><tr><td><div><div>`<NEW_WHATSAPP_USER_ID>`</div><div>*String*</div></div></td><td><div><div>New WhatsApp user ID. Note that a WhatsApp user's ID and phone number may not always match.</div></div></td><td><div><div>`12195555358`</div></div></td></tr><tr><td><div><div>`<NEW_WHATSAPP_USER_PHONE_NUMBER>`</div><div>*String*</div></div></td><td><div><div>New WhatsApp user phone number. Note that a WhatsApp user's phone number and ID may not always match.</div></div></td><td><div><div>`12195555358`</div></div></td></tr><tr><td><div><div>`<WEBHOOK_TRIGGER_TIMESTAMP>`</div><div>*String*</div></div></td><td><div><div>Unix timestamp indicating when the webhook was triggered.</div></div></td><td><div><div>`1739321024`</div></div></td></tr><tr><td><div><div>`<WHATSAPP_BUSINESS_ACCOUNT_ID>`</div><div>*String*</div></div></td><td><div><div>WhatsApp Business Account ID.</div></div></td><td><div><div>`102290129340398`</div></div></td></tr><tr><td><div><div>`<WHATSAPP_MESSAGE_ID>`</div><div>*String*</div></div></td><td><div><div>WhatsApp message ID.</div></div></td><td><div><div>`wamid.HBgLMTY1MDM4Nzk0MzkVAgASGBQzQUFERjg0NDEzNDdFODU3MUMxMAA=`</div></div></td></tr><tr><td><div><div>`<WHATSAPP_USER_PHONE_NUMBER>` *String*</div></div></td><td><div><div>WhatsApp user phone number. Note that a WhatsApp user's phone number and ID may not always match.</div></div></td><td><div><div>`16505551234`</div></div></td></tr><tr><td><div><div>`<WHATSAPP_USER_PROFILE_NAME>` *String*</div></div></td><td><div><div>WhatsApp user's name as it appears in their profile in the WhatsApp client.</div></div></td><td><div><div>`Sheena Nelson`</div></div></td></tr></tbody></table>

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