A button-down collar is ideal for more creating a more informal look and will go particularly well with a jumper. They’re versatile by nature and will work fully buttoned up or with the top button undone.
This striped version from Savoy Taylors Guild is made from 100% cotton to be both lightweight and breathable. It’s cut in a regular fit to provide comfort and a natural drape, with plenty of room available through the body and sleeves.
Keep an open neck and pair with some dark blue suit trousers for an easy-going, smart-casual appearance.