A casual shirt is a relaxed, versatile top for everyday wear, defined by comfortable fabrics (like denim, linen, flannel), softer collars (button-down, band), looser fits, and bolder colors/patterns, designed to be worn untucked for a laid-back, stylish look in informal settings. 

Key characteristics

Fabric: More varied textures like oxford cloth, chambray, flannel, denim, linen, or soft cotton blends, offering breathability and comfort.

Fit: Looser, more generous cuts compared to fitted dress shirts, allowing for ease of movement.

Collar: Softer, often button-down, grandad (band), or camp collars, suitable for tie-less wear.

Hem: Shorter length with a shirt-tail hem, intended to look good untucked.

Details: May feature chest pockets, contrasting stitching, or logos.

Colors & Patterns: Wide range of options, from bright solids and florals to checks and stripes, allowing for personal expression.

When to wear

Social gatherings, weekend outings, travel, or casual Fridays at work.

Paired with jeans, chinos, or shorts for a comfortable yet put-together appearance.