Mail app on Mac OS X is a great interface like outlook on windows. If you didn’t try or not using Mail app then must use and take advance mail option that not available for each Email services. In that One of the most popular settings that you can manage by change fetch new mail auto time on Mac OS X EI Capitan, OS X Yosemite.
Notification pop up on your Mac Screen will be appeared at top right corner, When new mail comes to your address. Without re login you can access multiple mail account with single app securely.
Also access all mail auto saved on your Mac’s Drive, when you are offline or poor internet connection. in that case you can manage time interval for check new incoming mail from multiple option. go with below easy steps on your Mac, MacBook, MacBook Pro or Air.
Steps for Change fetch new mail auto time on Mac OS X: EI Capitan, OS X Yosemite
Step 1: Go to the Mail app on Mac or Search Mail in Spotlight search.
Step 2: From top menu Under the Mail > Preference.
Choose time interval from Check new message, Never, Every Minute, Every five minute, Every hour, Every Thirty minute. 
Note: are you changing time interval due to some disappointed setting like notification sound and any reasons. Then share with us, we are happy to assist you. I Noticed many Mac user are change auto new message time interval due to notification sound, then you can update it under Mail > Preference > New message sound.
Useful: Set password on Mac Folder: Mac OS X
If you didn’t get new message automatically, Once go with above steps on change fetch new mail auto time on Mac and verify you shouldn’t choose never option from dropdown menu.