By default, when you create a 10DLC or toll-free campaign on Sendo, you will be assigned a single phone number to send messages from. However, you can easily add additional numbers to your campaign through the Sendo dashboard. To do this, open a campaign, navigate to the Numbers tab, and click “Add number” in the top right. Numbers can also be added using the /number/search and /number/buy API endpoints. Adding multiple numbers will not improve your messaging throughput or reduce the likelihood of spam filtering, as those limits are applied at the campaign level.
Note: Additional numbers cannot be added to toll-free campaigns

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Sending messages

If your campaign has multiple senders, you can specify which number to send from by including the from field in your /message/send API call. If you do not include this field, Sendo will send messages from your default sender. You can change your default sender on the dashboard by navigating to the Numbers tab for your campaign.
Note: Please ensure the from number is in format to avoid errors.
This is what your Numbers tab will look like if you have multiple senders:

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Webhooks

As of February 7th, when you create a webhook or modify an existing one, you can specify which phone numbers to send events for. This can be helpful if you have a number for internal testing, or if you want to send events to different URLs based on the sender.

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FAQs

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Why aren’t toll-free numbers supported?

Each individual toll-free number must undergo its own verification process, because of cell industry rules. Because of this, each toll-free campaign on Sendo can only have one number. For more toll-free numbers, you can create additional campaigns.

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Are there any fees for additional numbers?

There is a recurring charge of $2/month for each phone number attached to a campaign. This will be deducted from your balance at the same time as your campaign renewal charge. This applies to campaigns created with both 10DLC and toll-free numbers. When you purchase an additional phone number for a 10DLC (local) campaign, your balance will instantly be charged a prorated amount equal to the number of days remaining until the campaign renews. Please contact support if you have any billing questions.

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Is there a limit on the number of senders I can have?

By default, a campaign can have a maximum of 50 associated phone numbers. However, this limit can be increased upon request. There may be some additional charges. Please contact support if you need to add more than 50 phone numbers to a campaign.

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Can I place a bulk order of phone numbers?

Yes, please contact support if you would like to purchase a large batch of phone numbers. We can easily accomodate this request. Please provide us with the campaign ID, the number of phone numbers you would like to purchase, and any preferred area code(s).