# 1-way SMS communication

**1-way** SMS communication involves **sending** messages only, i.e., customers cannot reply to the messages sent by your business.  

{% hint style="warning" %}
**Note:** 1-way messaging is not allowed in some countries (e.g., the USA).
{% endhint %}

To engage in 1-way SMS communication, you do **not** require a dedicated number. 

When selecting 1-way messaging as part of the [SMS setup wizard](/sms-channel/getting-started/add-new-sms-setups-self-serve.md), you are **not** required to purchase a long number/short code, and a **random number** will be used as the *from* number.

{% hint style="success" %}
Learn how to send 1-way messages using [One API](https://docs.clickatell.com/channels/one-api/one-api-reference/#tag/One-API/operation/sendMessageREST).
{% endhint %}


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