You can try this:
Whitelist a Domain in Mac OS X Mail
To put a complete domain on your Mac OS X Mail white list:
Select Mail | Preferences... from the menu in Mac OS X Mail.
Go to the Rules category.
Click Add Rule.
Type a Description:, such as "Whitelist: example.com".
Make sure the criteria read: If any of the following conditions are met: From Ends with.
Enter the domain name you want to whitelist after Ends with.
◦ You can add a '@' sign before to make the filter more specific. To whitelist all mail from the "example.com" domain ("heinz@example.com") but not from its sub-domains ("heinz@heinz.example.com"), for instance, type "@example.com").
◦ Of course, you can filter multiple domains with one rule. Click the plus sign next to the last condition and add another domain with the same criteria. Maybe add the additional name to the rule Description, too.
Make the actions read: Perform the following actions: Move Message to mailbox: Inbox.
◦ You can also choose a different target folder, of course.
Click OK.
Make sure the rule is executed before other rules that might act on the same message for other reasons by dragging it near the top of the rules list.
◦ If you have a filter that color-codes certain messages based on keywords in the subject, for example, make sure the domain whitelist rule is above that labeling rule.
Close the Rules window.
