Your default printer is the one your Mac automatically uses when you print. Setting this correctly prevents printing to the wrong device.

Click the Apple menu () in the top left corner 

Select System Settings

Select Printers & Scanners

Select the "Default printer" dropdown and choose one of the following:

• A specific printer that will stay as your default Printer.  This printer will always be selected, unless you manually change it.
• "Last Printer Used," which changes automatically based on your most recent print job.

What to expect:
    •    Your selected printer will now be the default whenever you print.
    •    You can still choose a different printer manually if needed.

Important note:
    •    Your default printer will not automatically change just because you manually select a different print in a print dialog box.
    •    If you want it to change automatically, select “Last Printer Used” instead.

If you don’t see the printer you want, you may need to install it first using Self Service+.  Select here for the knowledge base article on installing additional printers.