> For the complete documentation index, see [llms.txt](https://help.recart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.recart.com/developers/public-api/subscription/initiate-sms-subscription.md).

# Initiate SMS subscription

Trigger an SMS subscription flow in Recart. It sends the associated welcome flow to the recipient. Flow must be active to comply TCPA regulations.

```json
{"openapi":"3.1.0","info":{"title":"Recart API","version":"2023-12"},"tags":[{"name":"Subscription","description":"Subscriptions"}],"servers":[{"url":"https://api.recart.com/app-integrations/2023-12","description":"Production"}],"security":[{"ApiKeyAuth":[]}],"components":{"securitySchemes":{"ApiKeyAuth":{"type":"apiKey","in":"header","name":"X-Recart-API-Key","description":"It can be obtained in Recart account after contacting Support"}},"schemas":{"PostSubscription":{"type":"object","required":["type","attributes"],"properties":{"type":{"type":"string","enum":["subscriptions"]},"attributes":{"type":"object","description":"Attributes of the subscriber","required":["phoneNumber","source"],"properties":{"phoneNumber":{"type":"string","description":"Preferably E.164 format"},"source":{"type":"object","required":["category","name"],"properties":{"category":{"type":"string","description":"Source category"},"name":{"type":"string","description":"Source name"},"externalId":{"type":"string","description":"Optional identifier"}}},"browser":{"type":"object","properties":{"userAgent":{"type":"string","description":"User agent of the browser"},"language":{"type":"string","description":"Language of the browser"},"url":{"type":"string","format":"uri","description":"URL of the browser page"}}},"sessionId":{"type":"string","description":"Recart identifier of the purchase session.  Use `_recart.getSessionId()` on the merchant's store when Recart script is running."},"shopperId":{"type":"string","deprecated":true,"description":"Deprecated: the `_recart.getShopperId()` method used to source this value has been removed and there is no replacement. This field is retained for backward compatibility but should no longer be relied upon."},"firstName":{"type":"string","description":"First name of the subscriber"},"lastName":{"type":"string","description":"Last name of the subscriber"},"timezone":{"type":"string","description":"Timezone of the subscriber"},"location":{"type":"object","properties":{"city":{"type":"string","description":"City"},"province":{"type":"string","description":"Province"},"zip":{"type":"string","description":"ZIP code"},"country":{"type":"string","description":"Country"},"ipAddress":{"type":"string","format":"ipv4","description":"IP address of the subscriber"}}}}}}},"HttpErrorBody":{"type":"object","required":["errors"],"properties":{"errors":{"type":"array","items":{"type":"object","required":["id","code","title","detail"],"properties":{"id":{"type":"string"},"code":{"type":"string"},"title":{"type":"string"},"detail":{"type":"string"}}}}}}},"responses":{"HttpError":{"description":"HTTP Error response","content":{"application/vnd.api+json":{"schema":{"$ref":"#/components/schemas/HttpErrorBody"}}}}}},"paths":{"/subscriptions":{"post":{"summary":"Initiate SMS subscription","tags":["Subscription"],"operationId":"postSubscription","description":"Trigger an SMS subscription flow in Recart. It sends the associated welcome flow to the recipient. Flow must be active to comply TCPA regulations.\n","requestBody":{"required":true,"content":{"application/vnd.api+json":{"schema":{"type":"object","properties":{"data":{"$ref":"#/components/schemas/PostSubscription"}}}}}},"responses":{"202":{"description":"Accepted"},"4XX":{"$ref":"#/components/responses/HttpError"},"5XX":{"$ref":"#/components/responses/HttpError"}}}}}}
```


---

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