What IP addresses are used for connecting to the provider / delivering mail to the provider?

Nylas has a large pool of IP addresses that are used to connect to the provider and to collect mail and deliver mail to the SMTP server. The provider may need to whitelist these IP addresses, this is especially common with IMAP and SMTP servers.

To find these IP addresses the developer of the application needs to retrieve them using our API endpoint and pass these onto the customer's mail administrator.

Alternatively 

The mail administrator of the server / provider can whitelist all the AWS IP addresses. Please refer to the instructions in the following article: AWS Public IP Address Ranges Now Available in JSON Form.

If the application is hosted in the US:

• You should whitelist all IP ranges designated as "us-west-2" in the JSON file. This file is available on the Amazon AWS site of IPs.

If the application is hosted in the EU:

• You should whitelist all IP ranges designated as "eu-west-1" in the JSON file. This file is available on the Amazon AWS site of IPs.

Resources:

Return Application IP Addresses API endpoint

Updated May 25, 2023 17:12