Dress necklines: sweetheart, bateau, halter and more

The neckline shapes, drawn

The neckline is the top edge of a garment around the neck and shoulders. Necklines are grouped by their shape — curved, straight, V or U — and by where they cut across the body: high on the collarbones, across the chest, or below the shoulders.

How a strapless dress stays up

A strapless bodice has no visible support, so it is held by its own fit: usually an internal corset or built-in bra, with boning, and a bodice tight enough not to slip. Since the 1980s some strapless dresses have been made in stretch fabrics that need no boning, but a fitted formal gown usually still relies on structure inside.

• Fit at the top edge. The bodice should sit firmly against the body when you raise your arms and when you sit; gaping at the top edge means it needs taking in.
• Weight below. A heavy skirt pulls a strapless bodice down. Ask whether the gown has a waist stay — an inner band that carries the weight at the waist.
• Options later. Detachable straps or a light jacket can be added for the ceremony and removed for the reception.

High and wide: bateau, square and illusion

A bateau or boat neck runs almost horizontally, front and back, nearly to the points of the shoulders. It came from the striped shirts of French sailors — a French Navy uniform used it in 1858 — and moved into evening wear as a clean, covered line. A square neckline has three straight edges and has been used on wedding dresses since at least the 1800s.

The illusion neckline is a compromise between low and high: a low, often strapless neckline with sheer tulle or lace laid above it, which draws a second, higher neckline. It is often seen on traditional white wedding dresses, and works where a church or family expects covered shoulders.

Shoulders and back: off-the-shoulder, halter and one-shoulder

An off-the-shoulder neckline sits lower than a boat neck, below the shoulders and collarbone; it was the height of fashion in the early to mid-19th century. A halter has a V or scoop front with a strap that ties or fastens behind the neck, so it covers the chest, shows the collarbone and usually leaves the upper back bare — the strap can even be hidden under the hair. A one-shoulder neckline cuts diagonally from one shoulder to under the other arm.

V-neck, scoop and sweetheart

A V-neck is formed by two diagonal lines meeting on the chest, and a scoop by a curved U; both range from high to plunging, and evening gowns often cut them low. A sweetheart neckline has a curved, doubly scalloped lower edge like the top half of a heart. It accentuates the bust, and its strapless version is common on wedding dresses.

Any of these can be changed: layering tulle or lace over a low neckline turns it into an illusion neckline, and edges can be finished with scallops, beading or ruffles. A neckline is also easier to raise with an overlay than a hem is to lengthen, so it is worth discussing early with whoever alters the dress.