Messages API (Email channel) - Features & Capabilities FAQs

1. Can I get a dedicated IP address?

Dedicated IP is now available at GA for customers needing reputation isolation, included free of charge with Advanced plans.

2. How does Vonage manage domain and IP reputation?

Vonage ensures that each customer's domain reputation is isolated. One domain's reputation does not affect another. In addition, Vonage manages a suppression list for your domain to protect your sender reputation.

3. What is a suppression list?

A suppression list is a feature that is enabled by default for your domain. It automatically adds recipients to a block list if they generate a hard bounce or mark your email as spam, preventing further emails from being sent to those addresses. This protects your domain's sender reputation

4. Does Vonage support CC and BCC?

Yes. CC and BCC are now supported and available as a default option for all customers at no additional cost.

5. Does Vonage support attachments and unsubscribe features? 

Attachments: Support is planned for Q4 2026.

Unsubscribe Management (one-click unsubscribe, consent service, category-level opt-out): Planned for Q1 2027.

6. What is the maximum email size I can send via the Vonage Email API? 

The maximum email body size is 100 KB. Attachments are not currently supported, so this limit applies to the email body only.

Q7. Can I send an email to multiple recipients?

Yes. Multiple recipients are supported:

• To: Only one recipient address is supported
• CC and BCC: Each can be an array of addresses
• Total recipients across To, CC, and BCC: up to 40 recipients per request

8. Can I receive inbound emails on my domain? 

Yes. Inbound emails are now supported. You can receive inbound mail on your verified domain via the inbound webhook.

9. What factors affect my email deliverability?

Email deliverability depends on shared responsibilities between Vonage and the customer:  

Domain Authentication (SPF, DKIM, DMARC)  
Sender Reputation - avoid spam complaints, high bounce rates, sudden volume spikes  
Email Content Quality - avoid broken links, oversized payloads  
Recipient Engagement - opens, clicks, replies improve reputation  
Bounce Management - Vonage auto-suppresses hard bounces  
List Quality - never use purchased lists, regularly clean inactive recipients