The biggest difference between a sofa and a loveseat is size; sofas are nearly always larger than loveseats. In addition, a sofa may have additional features such as a pull-out bed, whereas a loveseat will very rarely include this feature, because they are simply not large enough for it to be practical. A sectional sofa is a common piece of furniture used in a large living room, but a sectional loveseat simply does not exist. Many people will purchase a matching sofa and a loveseat at the same time, because the fabric can be selected to match, and together they will give a living room or family room a comfortable, cohesive look.
Though the size differences in a sofa and a loveseat can vary, typically a standard sofa will comfortably seat three people, on three different cushions, while a loveseat will usually only seat two. A loveseat is styled much more similarly to an oversized chair than a couch. Larger sofas may seat six people or more, particularly sectional sofas, which may be pulled apart or put into a corner, with each section of the sofa extending down a different wall. A loveseat will simply not include different sections like this.
Another important difference between a sofa and a loveseat is the capability of a sofa to accommodate a pull-out bed or other additional features. Often, sofas will feature a small, thin mattress that can be folded up inside the sofa when not in use, and extended at night for sleeping. Loveseats are generally too small to feature a fold-out bed. Some sofas will also offer reclining seats that are somewhat separate from the rest of the cushions, but a loveseat will typically not include this capability. This is not always the case, however.
A sofa and a loveseat are often purchased together for a living room or family room. Sometimes loveseats in matching sets are considered to be fancier pieces of furniture than a stand-alone sofa or couch, and may be placed in a more formal sitting room. Many people purchase these pieces of furniture together so that the fabrics will match, as it is often possible to order custom fabric to match the decor in the rest of the home. Regardless, sofas and loveseats are some of the most common pieces of furniture that are found in many different types of homes in a variety of areas around the world.