Allowlist our IP addresses

If you use a firewall or an allowlist, you may need to allow traffic from our IP addresses to support traffic from Customer.io based on the features you use.

If you use a custom SMTP server, webhooks, Reverse ETL, our Salesforce integration, or an outgoing data warehouse integration, you may need to allow our IP addresses to support traffic from Customer.io.

Some IP addresses depend on your account region.

Email (Custom SMTP) and Webhook IP Addresses
US RegionEU Region
35.188.196.18334.76.143.229
104.198.177.21934.78.91.47
104.154.232.8734.77.94.252
130.211.229.19535.187.188.242
104.198.221.2434.78.122.90
104.197.27.1535.195.137.235
35.194.9.154130.211.108.156
104.154.144.51104.199.50.18
104.197.210.1234.78.44.80
35.225.6.7335.205.31.154
136.111.237.15735.187.55.80
34.10.127.179104.199.99.65
35.184.88.7634.76.81.2
34.72.101.5734.77.146.181
34.123.199.3334.140.234.108
35.222.137.6135.240.84.170
34.68.113.6335.195.54.15
35.224.76.1634.38.105.52
34.171.255.93104.155.66.230
35.202.181.5434.76.119.61
104.197.234.6934.140.67.73
34.27.147.3334.78.74.81
104.198.142.4434.77.77.112
34.67.123.3335.195.63.136
34.46.170.22834.14.49.179
34.136.83.254207.175.117.181
35.226.154.9834.156.15.255
34.10.194.61104.155.22.76
34.9.172.87104.199.11.206
104.154.26.10835.233.57.249
34.46.73.137207.175.115.145
35.223.111.25334.14.1.70
136.116.152.25234.52.153.127
35.223.42.14434.140.238.61
35.254.140.10035.205.103.251
34.173.62.14335.240.116.82
136.113.81.10734.62.52.238
136.116.213.7735.195.75.68
136.80.34.90
104.154.48.9
35.222.138.66
35.193.138.112
34.59.154.157
34.59.143.43
35.193.105.125
35.224.88.104
34.42.107.95
34.58.120.43
35.184.74.94
Reverse ETL IP Addresses (data-in)
US RegionEU Region
34.29.50.434.22.168.136
35.222.130.20934.78.194.61
34.122.196.49104.155.37.221
34.9.152.5334.78.153.242
34.170.216.13134.78.94.137
35.222.84.13134.140.151.135
34.57.129.12734.62.147.132
Salesforce IP Addresses
US RegionEU Region
34.29.50.434.22.168.136
35.222.130.20934.78.194.61
34.9.152.5334.78.153.242
34.170.216.13134.78.94.137
35.222.84.13134.140.151.135
34.57.129.12734.62.147.132
Data Warehouse IP Addresses (data-out)
US RegionEU Region
34.71.192.24534.118.255.179
35.188.196.18334.76.143.229
104.198.177.21934.78.91.47
35.184.88.7635.187.55.80
34.72.101.57104.199.99.65
34.123.199.3334.76.81.2
35.222.137.6134.77.146.181
34.68.113.6334.140.234.108
35.240.84.170
35.195.54.15
34.38.105.52
104.155.66.230
34.76.119.61
34.140.67.73
34.78.74.81
Updated October 16, 2026