Outreach will connect to your SMTP server from the following IP addresses:
app1a - 184.108.40.206, 220.127.116.11
app1b - 18.104.22.168, 22.214.171.124
app1c - 126.96.36.199, 188.8.131.52
app1d - 184.108.40.206, 220.127.116.11
app1e - 18.104.22.168, 22.214.171.124
app2a - 126.96.36.199, 188.8.131.52
The source IP addresses above are the same for the connectivity to retrieve email using Exchange Web Services (EWS).
You'll be able to see which addresses you'll use by checking the address bar of your browser when connected to Outreach:
Note that this is NOT the IP address your email is sent from; that will be determined by your outbound email provider (Gmail, Sendgrid, etc.). You will only need these addresses if your outbound (SMTP) mail server needs to whitelist inbound connections that can give it mail to send.
If you need information about the IP addresses your mail is sent from, you'll need to check with your mail provider. You can see more about this in our article on SPF and DKIM here.