The default font in any new PowerPoint presentation is Arial, 18
pt, black, for text boxes other than the ones that are part of
the default design template such as the Title text box and
Bulleted list text boxes. If you are making a new PowerPoint
presentation and do not want to have to change the font each
time you add a new text box the solution is simple. - Click on
any blank area of the slide or outside the slide. You want to
make sure that no object on the slide is selected. - Choose
Format > Font... and make your selections for font style, color,
size and type. - Click OK when you have made all your changes.
Test out your changes by creating a new text box. The new text
box should reflect the new font choice. Change Fonts for Other
Text Boxes To make changes to the fonts used for titles or other
text boxes that are part of each template, you need to make
those changes in the Master Slides.