Although go-to classics like T-shirts, tank tops, button-down shirts and turtlenecks in both tailored and fluid fits are great to layer under all sorts of jacket styles — you have more options. The top styles below are particularly popular with my business casual clients because they drape well under jackets and the necklines are complementary. They can also be worn in casual settings with jeans, in solids or in patterns. 

I’ve provided examples for each type of top, but there are many, many versions to choose from at retail. Choose dressier fabrics for business casual environments. 

1. Boat Neck Top

Boat necks can fit close to the neck like the example on the left, which I call a “slash neck”. Or they can fit a little wider around the neck like the example on the right. They are available in both knits and wovens, although I’ve found a knitted boat neck to layer more neatly under a jacket because it’s stretchy. Slash necks are particularly well suited to long necked ladies, ladies with a small bust, or those with sloping shoulders. 

Vince Boatneck TeeEileen Fisher Bateau Neck Organic Linen Top

2. Diagonal Sleeve Blouse

The diagonal sleeve is magical and not to be confused with cap sleeves, which are a tighter and shorter style. Choose a diagonal sleeve blouse with a crew neck, V-neck or boat neck in a woven or knit for jacket layering. The V-neck diagonal sleeve blouse is especially flattering on a large bust.

Reiss Ellie PrintClassiques Entier Woven & Jersey V-Neck Top

3. Drape Front Blouse

This is the most on-trend option here, but you have to be at peace with the excess volume around the midsection. The V-neck drape front blouse, which is referred to by some retailers as a wrap-front blouse, works extremely well under a tailored blazer with a low stance. Modern and fresh, adding a little loose arty drape to the severity of the blazer. 

They are nice in knits and wovens. You might need to size down to rein in the volume, and use fashion tape to prevent the fronts from falling open. I sewed in press studs to keep the fronts closed, and of course, wear the style with a camisole. 

Vince Camuto Sleeveless Wrap Front Shirttail BlouseHelmut Lang Raglan Sleeve Drape Front Blouse

4. Sleeveless Silky Shell Top

Simple and effective, especially in a shade of solid white, a bright, a graphic or a floral pattern. I’ve shown V-necks, but they’re just as good in crew and scoop necks, so pick your preference. Sleeveless tops are extra streamlined under jackets because they eliminate bunching. But unless you’re fine with baring your arms, they limit the removal of the jacket. Choose one in a fluid fit.

Vince Camuto Sleeveless V-Neck BlouseBanana Republic Rope Print V-Neck Tank

Wear these tops untucked, fully tucked or partially tucked with trousers, cropped pants, pencil skirts or jeans. The first three styles are especially good when you need the flexibility of removing your jacket. The sleeveless top is less flexible, but sometimes a jacket looks best styled with a very simple under layer, so they have their place. 

Classic wrap tops with side ruching are still a good choice under jackets, although they’re harder to find because most are formfitting. And formfitting tops at the moment are not as fashionable as ones with a fluid or oversized fit.