Sofa Cushion Filling: What Works Best and How to Choose

When you sit down on a sofa, what you’re really feeling is the sofa cushion filling, the inner material that gives support, comfort, and shape to your seating. Also known as cushion core, it’s the hidden piece that decides whether your sofa feels like a cloud or a brick after just a few months. Most people focus on fabric or style, but the filling is what actually wears out first—and it’s the biggest reason why budget sofas collapse while others last a decade.

There are three main types of filling you’ll find: high resilience foam, a dense, bouncy material that holds its shape for years and is often used in mid-to-high-end sofas, polyester fill, a soft, fluffy material that feels cozy at first but flattens quickly under regular use, and down and feather blends, luxurious and moldable, but require constant fluffing and aren’t ideal for households with kids or pets. High resilience foam is the most durable choice for daily use. Polyester fill is cheap and common in discount stores, but it turns into a flat pancake after 1–2 years. Down feels amazing but needs serious upkeep.

The cover fabric matters too. A tight weave keeps filling from escaping and adds structure. Loose weaves let foam bits and polyester clumps shift around, making your sofa lumpy. Look for removable, zippered covers—those are a sign the manufacturer expected you to replace the filling later. Also, check the density rating if it’s listed: 25–35 kg/m³ is decent for foam, anything below 20 is low quality.

Most people don’t realize their sofa’s filling can be replaced. You don’t have to buy a whole new couch if the frame is still solid. Re-filling cushions costs a fraction of a new sofa and brings it back to life. Many local upholstery shops offer this service, and some even let you choose the foam density. If you’re handy, you can do it yourself with foam blocks from a hardware store.

What you’re looking at here is a collection of real-world tests, user experiences, and expert breakdowns on what actually holds up over time. You’ll find guides on which cushion materials last the longest, how to spot a cheap fill before you buy, and why some sofas go flat while others still feel new after five years. Whether you’re shopping for a new sofa, fixing an old one, or just tired of sinking into your couch, the posts below give you the facts—not the marketing.