Here are the steps to add your favorite mail addresses to your whitelist and get them delivered straight to your Inbox. Let’s consider Gmail and Yahoo! mail as they are the most commonly used mail services.
Gmail Users :
1. Follow the Settings link in your Gmail.
2. Go to Filters and click Create a new filter
3. Under ‘From’ field, type the desired address you want to be whitelisted.
(let’s say info@bloggersbase.com)
4. If you want to whitelist all the mails from bloggersbase then you can just type the domain name or the domain name preceded by ‘@’. So, if you wanna whitelist all the mails from bloggersbase.com domain then just type @bloggersbase.com
5. Test search your entry and click on Next Step >>
6. Now, check the box that says “Never send it to Spam” and click Create Filter
That’s it!!
Yahoomail Users do as below :
1. Login to your account and go to Yahoo! mailbox.
2. Click “Options” & navigate to the Mail Options page.
3. Click on “Filters” under Management.
4. Now, click “Add” button 
5. In the field named “From Header:” make sure “contains” is selected.
6. Click in the text box next to that drop-down menu, and enter the address you want to be whitelisted.
7. At the bottom, where it says “Move the message to:” select “Inbox” from drop down the menu.
8. Click the “Add Filter” button at the bottom.
That’s it!! You have successfully added your message filter.