Setting Up CritSend's SMTP Relay or API

There are two ways to connect to CritSend - using our easy enhanced SMTP relay or using our API. See CritSend's API doc page for API info and examples.

Our SMTP gateway is easiest to configure. Our API is best if you need tighter integration or if you are building a new delivery service and from scratch and are more advanced.

Quick Setup

Advanced: How To Send from YourDomain.com (domain whitelisting and transparency)

Extra Tips, Tricks & Features

• How To Make Sure Your Mails are Legally Compliant
• Want to know which of your emails are performing well and which could use improvement? Tag Them!
• Easy Unsubscription Handling