Below is a list of IPs you can add to your firewall for sending transactional email through SMTP, Inbound processing and Webhooks.
Outbound SMTP Servers #
The IP addresses that Transactional and Broadcast messages are sent from.
- 50.31.156.96/27 (50.31.156.96 - 127) [Transactional]
- 104.245.209.192/26 (104.245.209.192 - 255) [Transactional]
- 50.31.205.0/24 (50.31.205.1 - 255) [Broadcast]
SMTP Endpoints #
The IP endpoints for accessing SMTP outbound.
CIDR Blocks / Ranges
- 147.75.195.176/30 [147.75.195.176 - 147.75.195.179]
- 147.75.202.84/30 [147.75.202.84 -147.75.202.87]
- 147.75.205.84/30 [147.75.205.84 - 147.75.205.87]
- 52.79.88.220
- 54.180.186.193
- 34.249.162.51
- 52.208.184.61
- 63.35.51.189
- 3.208.98.158
- 3.93.205.235
- 3.95.122.1
- 3.208.98.158
- 3.93.205.235
- 3.95.122.1
- 13.209.189.43
- 15.164.159.110
- 52.208.94.138
- 52.210.34.36
- 54.77.222.65
Inbound SMTP Servers #
These IPs are where Postmark's inbound MX record points.
- 13.58.75.120
- 52.36.8.247
- 18.221.96.15
- 34.211.250.229
- 34.211.88.250
- 18.221.180.145
- 52.210.157.196
- 52.213.211.243
- 52.51.73.41
- 13.125.126.102
- 3.34.204.228
- 3.34.213.247
- 107.22.71.110
- 52.2.5.255
- 72.44.42.226
Webhooks #
These IPs apply for every webhook sent by Postmark (inbound, bounce, open, etc).
- 3.134.147.250 (New - added 9/15/2020)
- 50.31.156.6
- 50.31.156.77
- 18.217.206.57