The layer between the sheet and the duvet has several names that describe genuinely different objects, and choosing the right one changes how a bed works.

The Definitions

A blanket is a single layer of woven fabric, usually cotton or wool, with no filling. Its warmth comes from the fibre and the weave.

A coverlet is a lightweight quilted or woven cover, typically sized to cover the top of the bed without hanging to the floor. It is a top layer as much as a warmth layer.

A quilt has a filling stitched between two layers of fabric, which traps air and provides more warmth for its weight.

What Each Is For

• Cotton blanket: light warmth, breathable, good in summer alone
• Wool blanket: considerably warmer, heavier, excellent temperature regulation
• Coverlet: a finishing layer, warmth secondary
• Quilt: warmth for its weight, and a defined look
• Duvet: the main warmth layer in most modern beds

Ranges making blankets in the same cotton as the sheets, of the kind at threadmill-us.com, are aiming at the layer that adjusts a bed rather than one that dominates it.

The Case for a Cotton Blanket

The most useful and least fashionable item in a bedroom.

It adds a small amount of warmth without adding much heat retention, which is exactly what most beds need on the nights between seasons. A duvet is either on or off; a blanket adjusts.

It also breathes, so it does not produce the clammy feeling a synthetic throw does.

Layering Beats One Heavy Thing

The principle from outdoor clothing, and it applies to beds.

Several thin layers trap air between them and can be adjusted individually. One thick layer is a single decision made in advance.

A sheet, a blanket and a light duvet covers a wider range of nights than one heavy duvet does.

Waffle and Herringbone Weaves

Both are structures that trap air in the weave itself, so a cotton blanket can be warmer than its weight suggests.

They also drape well and launder easily, which is why they persist.

Washing

Cotton blankets machine wash, which is a real advantage over wool and over most quilts.

Cool wash, low heat, no fabric softener. Wool needs specific care and frequently professional cleaning.

Sizing

Blankets are sized to the bed rather than to the duvet, and a blanket that does not tuck or drape properly looks wrong.

Check the finished dimensions rather than the size name.

At the Foot of the Bed

The practical arrangement: folded across the end, pulled up when needed.