# Customizing delivery for large mailbox providers

To send your mail using [Velocity MTA delivery policy settings](https://docs.emaildelivery.com/docs/velocity-mta-basics/creating-an-mta-delivery-policy) customized for prominent mailbox providers such as Gmail, Yahoo, Outlook, etc:

First, create [domain groups](https://docs.emaildelivery.com/docs/advanced-postal-route-configuration/contact-list-domain-routing) for your postal routes, then use postal route [load balancing](https://docs.emaildelivery.com/docs/advanced-postal-route-configuration/load-balancing). 

Alternatively, you can break large domains such as Gmail out into their own broadcasts or email funnels using a separate postal route, and create a second broadcast or funnel for the rest of your list. 

This could be accomplished by sending through separate postal routes using contact list [segments](https://docs.emaildelivery.com/docs/segmenting).