What to wear under a blazer: tops that sit flat

Necklines that sit inside the lapels

Lapels already make a strong shape at the neck, so the top should either fill the V quietly or sit just above it.

• Crew and [round necks](/styles/necklines/round-neck). The most reliable choice; they frame the lapels without competing.
• A shallow [V-neck](/styles/necklines/v-neck). Echoes the lapels. Keep it shallower than the jacket’s opening so the two Vs do not stack.
• A [boat neck](/styles/necklines/boat-neck). Elegant under a one-button blazer, provided it is not so wide that it shows at the shoulders.
• A band collar. Neat and covered, and especially good under a collarless or edge-to-edge jacket.
• Bows, ruffles and big collars. Striking, but they crowd a notched lapel. Pair them with a collarless jacket or wear the blazer open.

Sleeves are the usual source of bulk

Blazer sleeves are cut close to the arm, and anything thicker than a fine knit underneath bunches at the elbow and drags the jacket sleeve tight. That is why so many work tops are sleeveless or short-sleeved: a shell leaves the jacket’s sleeves free. If you want covered arms for when the jacket comes off, choose a thin, close sleeve in a smooth fabric, and skip puffs, bells and elastic cuffs that gather into a lump at the wrist.

Smooth fabrics help too. A top in crepe, viscose or a silky woven slides in and out of a lined sleeve, while brushed or textured cotton grips the lining and twists.

Hem length and tucking

Match the top to the blazer you actually own. Measure from the base of your neck to where the blazer ends, then decide whether the top should be tucked, the same length or clearly longer.

• Tucked in. The tidiest with high-waisted trousers or skirts. The top needs enough length to stay tucked when you reach up.
• Ending at the hip. A straight hem at the top of the hip lies flat under most hip-length blazers.
• Clearly longer. A long tunic under a cropped jacket can look deliberate, but a top peeping out a few centimetres below the jacket usually looks like an accident.

Why a made-to-measure shell top works

A shell top is a simple sleeveless or short-sleeved top with a plain neckline, usually in a smooth woven fabric, made to sit under jackets. With so few details, fit is everything: armholes close enough not to gape, a neckline that sits where your blazer opens, and a length that suits your jacket. Ready-made shells often get one of those wrong.

You can order Western tops through custom stitching: choose the neckline and sleeves on the form, give your blazer’s length in the notes, and add a photo if you have a shape in mind. Two or three in quiet colours, such as ivory, navy, black or soft grey, cover most suits. Request a quote and we confirm the fabric and details in writing before cutting. For complete work outfits, see our modest workwear guide.