Horizontal vs Vertical Buttonholes

When the buttonhole is ¾” or less, vertical or horizontal buttonholes are both good choices. When the buttonhole is larger than ¾”, Suzy recommends using a horizontal buttonhole, because vertical buttonholes become unstable at that length.

Not only does the button slide up and down within the buttonhole, potentially causing the shirt to look uneven, but the weight of the thread may make the vertical buttonhole gape or droop.

Suzy also discusses when to use a bound buttonhole. When the buttonhole needs to be larger than 1 ⅜”, Suzy recommends using a bound buttonhole, because creating such a large opening weakens the fabric, and a bound buttonhole helps stabilize that opening.

Suzy also discusses the difference between the terms “button down” and “button up” when describing a shirt, and looks at an example of a shirt that combines horizontal and vertical buttonholes.

For more on buttonholes, check out these videos:
Sewing Buttonholes and Buttons
How to Use a Buttonhole Foot
Bound Buttonholes Made Easy