In the past, when headshots were more commonly printed on paper and handed out in person, they were exclusively printed on 8×10 paper. Now, headshots are shared digitally most often, and as a result the crop/aspect ratio of headshots has changed. Though headshots must still be printed on 8×10 paper if they are printed at all, the size/crop of the image itself can vary. Some find an 8×10 crop to be less flattering as it tends to show more of the actor’s shoulders, etc.

It is important to choose the option that you think will work best for you personally. I have not found any consensus in the industry as to what is expected anymore. If you already have an agent, you might ask their preference.

4x6 Cropped Headshot

Though the crop is not the traditional 8x10, it is effectively drawing focus to the actor's face and eyes as a result of the tighter crop. If choosing this option, there will be a white border around the image if you decide to ever print it, as seen on the last example.

Traditional 8x10 Headshot

This image is 8x10, and therefore is printed directly on 8x10 paper without a border. Though it prints neatly, the crop on the actor is less focused on her face.

4x6 Image on 8x10 paper

Here, the 4x6 photo is being printed on an 8x10 sheet of paper. As this results in a white border surrounding the image, many actors print their name in the white space.