How to Plump Up Flat Sofa Cushions

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Flat Cushions Have Two Different Causes

Before fixing it, it's worth knowing which problem you actually have: the filling has genuinely compressed and lost volume over time (most common), or the cushion cover itself has stretched and is now too big for the filling inside it. The fix is different for each.


Method 1: Top Up the Existing Filling

If the cushion has an opening or zip, you can often add loose filling directly to what's already there — cheaper than buying a whole new insert and works well if the cover itself is still a good fit.

  1. Open the zip or seam if there is one.
  2. Pull the existing filling apart gently to loosen any compacted clumps.
  3. Add loose hollowfibre filling gradually, distributing it evenly rather than in one dense pocket.
  4. Close up and plump by hand until it holds its shape.

Method 2: Swap the Inner Pad Entirely

If the filling has broken down rather than just compressed — it feels lumpy or thin no matter how much you fluff it — a fresh bounce-back inner pad in the same size gives a cleaner result than topping up.


Which Product Do I Actually Need?

🥇 Gold Pick — 100% Confidence

Bounce-Back Cushion Inner Pads

The cleanest fix if the existing filling has broken down rather than just compressed.

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Silver Pick — Best Value

Hollowfibre Loose Cushion Stuffing

The cheaper option if you just need to top up filling that's still holding its shape.

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Honest Verdict

Try topping up first if the cover still fits well — it's the cheaper fix and often enough. Only go straight to a full inner pad swap if the filling's genuinely broken down, since it's a bigger cost for the same size of cushion.

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Related: Sofa Cushion Sagging: Why It Happens and How to Fix It · How to Make Sofa Cushions Firmer


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