Exchange Online IP Addresses

Up to date list can be viewed here:

https://technet.microsoft.com/en-us/library/dn163583(v=exchg.150).aspx

as of 2015-05-14 here is the list:

23.103.132.0/22 23.103.136.0/21 23.103.144.0/20 23.103.191.0/24 23.103.198.0/23 23.103.200.0/21 40.107.0.0/16 64.4.22.64/26 65.55.83.128/27 65.55.88.0/24 65.55.169.0/24 94.245.120.64/26 104.47.0.0/17 134.170.101.0/24 134.170.140.0/24 134.170.171.0/24 157.55.133.0/25 157.55.158.0/23 157.55.206.0/23 157.55.234.0/24 157.56.73.0/24 157.56.87.192/26 157.56.108.0/24 157.56.110.0/23 157.56.111.0/24 157.56.112.0/24 157.56.116.0/25 157.56.120.0/25 157.56.206.0/24 157.56.208.0/22 207.46.51.64/26 207.46.100.0/24 207.46.101.128/26 207.46.108.0/25 207.46.163.0/24 213.199.154.0/24 213.199.180.128/26 216.32.180.0/24 216.32.181.0/24