Can I use a Reserved IP address to send emails via SMTP?

Reserved IPs do not support SMTP traffic. All outbound SMTP traffic originates from the public IP address of the Droplet. You can find more details about the limits of reserved IPs at our Reserved IP Limits page.

Droplets do not have a dedicated IP address.
You cannot retain a Droplet’s IPv4 when you transfer the Droplet to a new region. Use a reserved IP address to maintain a static IP address.
Snapshots do not retain the IP address of the Droplet they were created from, but you can use reserved IPs to assign the same address to new or redeployed Droplets.