When should I update the Office 365 IP addresses in our network firewall ?

Frequent Contributor

Hi ,

 I understand that Microsoft releases the IP addresses for all the Office 365 services and that information can be viewed from the below mentioned URL . I would like to know when exactly am I supposed to make this change in the firewalls ? The effective date has been given for all the changes in the IP addresses , so am I supposed to make the change on the day before the effective date or what's the strategy behind this ? The approach that we have decided is to remove all the existing IP addresses in the firewall groups and replace them with the new set of IP addresses released by MS . Is that the right approach to follow ? Please check and let me know . 




5 Replies

Hi Vignesh,


What changes do you need to do ? And what services are needed.


Depending your firewall and services used, my approach is that you can start adding the new ip addresses before the effective date to avoid issues. After the change date monitor that the old addresses are not being used and then remove them from your firewall rule and groups.

No problem Vignesh. If you have any more questions, please ask here in the Community.

Hi ,

  Does Microsoft release these IP addresses for all the O365 services? Meaning , I would like to know whether MS releases these type of IP addresses for Microsoft flow too as Flow is built on top Azure Logic app service and these IP addresses have to point to those Azure data centers where Azure Logic app is built and running .