By default, if you have an OS X device that’s connected to both Ethernet and Wi-Fi, it should prioritize the Ethernet connection over the Wi-Fi one. Sometimes it gets wonky though, in which case you’ll always be on Wi-Fi no matter what.
How do you fix such an issue? The steps are actually quite simple. First, launch System Preferences (using Spotlight is fastest), then select Network:
At the bottom left of that window, look for the gear icon with the down arrow. Click on it to open the menu, then select Set Service Order:
Here you can drag-and-drop each item to change the priority order of your internet connections. Move Ethernet to the top to get the system to always use Ethernet over Wi-Fi when both are active. Wi-Fi will be a backup.
Click OK and then Apply and you’re done!
This is especially useful for when your Wi-Fi is unstable, but it’s also a good solution when your Wi-Fi is slow in general and there’s nothing you can do to improve the speed — when even this trick won’t work!
Do you have any other kinds of internet trouble on Mac OS X? Tell us about it in the comments, along with any solutions you may have.