The style of the back of a sofa or chair dramatically affects the design of the overall piece. Whether a sofa's back is tufted or tight or loose or scattered determines the style of your space. Do you want a casual, comfortable, "messy-chic" style? If so, you should consider a loose-backed sofa. Is your style more clean and refined? In that case you'd be more inclined to purchase a tight-backed sofa or chair. If you're going for a glamorous, textured look, a tufted back piece would be a great option for you. In the following, I'm going to list and describe the available back styles so that you can better understand your options and how to apply them in your own design!
 

Tight

The Tight-Back style features a back that is fully upholstered with no un-attached cushions. This style is often used in more formal applications and can be found in many modern and contemporary designs. Since Tight-Back sofas and chairs have no loose cushions, they maintain a crisp, clean appearance and provide firm support. The Hamlin Sofa by Ferguson Copeland (Below) is a beautiful Tight-Back style sofa. 

Channel

The Channel-Back style features large folds that run vertically along the back of the sofa, sometimes with a rolled decorative pattern. This style also has firm support and since it doesn't have loose cushions it will maintain its neat appearance as well. The Channel-Back style is a great way to give a room an elegant, fashionable texture that is easy to maintain. The Martine Settee by Dwell Studio (Below) is a gorgeous Channel-Back piece. 

Tufted

The Tufted-Back style features deep folds that are created by sewing buttons through the upholstery that create suggested square or diamond-like patterns across the piece. This style is most often found in formal room designs that exude elegance. The Whitney Sofa by Vanguard Furniture (Below) is a stunning Tufted-Back sofa. 

Attached Pillow

The Attached Pillow Back style is characterized by cushions that are sewn on to the frame. The cushions may appear to be loose, but they are not removable. The Attached Pillow Back style is a great way to create a neat and inviting, casual appearance without having to be constantly straightened. The Valencia Sectional by Weiman Preview (Below) is a gorgeous Attached Pillow Back style sectional sofa that exemplifies the crisp yet casual appearance that this style is known for. 

Loose 

The Loose-Back style typically includes two or three cushions that are unattached from the sofa or chair itself. The Loose-Back gives a piece a style that is more casual in appearance. Since the cushions are removable, they can conveniently be removed or reversed as needed. The Sheldon Sofa by Guy Chaddock (Below) is a beautiful Loose-Back style sofa. 

Pillow or Scatter

The Pillow or Scatter Back style consists of several individual pillows that provide cushioning for the back of the sofa or chair. This style gives a space a particularly inviting and comfortable appeal. The Pillow or Scatter Back style allows for flexibility in the design of your space as the pillows can be swapped out for others with different colors or patterns. The Monarch Sectional by American Leather (Below) is a great example of a Pillow or Scatter Back style sofa. The pillows are interchangeable which makes changing up the overall style of this sofa very easy!

T-Pillow

The T-Pillow Back style features cushions which extend over each arm to form a t-like shape and can be either loose or attached. This style is typically seen on casual, contemporary upholstery. The Danford Sofa by American Leather (Below) is a beautiful example of the T-Pillow Back style. 

Waterfall

The Waterfall-Back style features two or more vertical layers of gathered, billowing cushions that are attached to the back, providing a textured, grid-like look. This style fits in well with modern and contemporary styled rooms and offers great back support. The Waterfall-Back style is a great way to achieve the layered look of having multiple pillows without having to rearrange or straighten them. The Meyer Sofa by American Leather (Below) is a gorgeous, modern Waterfall-Back style sofa.