Glass Bead Weighted Blankets: Glass vs Plastic Pellet Fill

A glass bead weighted blanket uses tiny glass beads, sewn into small quilted pockets, to supply its weight. Compared with plastic pellets, glass is denser, so the blanket is thinner for the same weight, and the Sleep Foundation says it holds less heat. Plastic pellets feel warmer. Either kind washes by its own tag.

What is inside a glass bead weighted blanket?

Most weighted blankets are quilted. The shell is stitched into a grid of small pockets, and each pocket holds a measured amount of fill so the weight spreads evenly instead of sliding to one end. The fill is usually either micro glass beads, which look like fine sand, or plastic poly pellets, which are bigger. Some blankets add a layer of polyester batting around the beads for softness.

Knitted weighted blankets are the exception: their weight comes from thick yarn, with no beads at all. Our guide to cooling weighted blankets covers that style.

Glass beads vs plastic pellets

The two fills differ mainly in density, which changes how the blanket looks and how warm it sleeps.

Heat. The Sleep Foundation says cooling duvet-style weighted blankets typically use glass beads as fill, which hold less heat than plastic alternatives, and that micro glass beads tend to be more breathable and less bulky. It groups plastic pellets and natural grains with the warmer fills.

The case for plastic. Not every maker agrees glass is better. Mosaic, a weighted blanket company that uses plastic pellets, argues that glass beads can break down into finer particles over time, may clump when wet, and make a blanket harder to clean and dry. It describes its own pellet blankets as machine washable and dryer safe. Those are one seller’s claims about a fill it does not use, so weigh them alongside the care label on any blanket you consider.

Does glass bead fill change how heavy to go?

No. The weight rule is the same for every fill: makers suggest about 10 percent of your body weight. Glass only changes how thick the blanket is at that weight. Heavier blankets hold more body heat, the Sleep Foundation notes, so a hot sleeper may do better with a lighter glass bead blanket than with a heavier one. Our weighted blanket weight guide has the full chart.

How to wash a glass bead weighted blanket

Care varies by fill and maker, so the Sleep Foundation says to start with the tag or the manual. Its general advice for washable weighted blankets:

• Use a mild, bleach-free detergent and skip fabric softener.
• Choose cold or warm water and a gentle cycle, or hand wash.
• Check your washer’s weight limit. A wet weighted blanket is much heavier than a dry one; a commercial laundromat machine may be the safer choice.
• Dry it fully. Lay it flat and shake it now and then to spread the fill, or use a low to medium dryer setting if the tag allows.

A removable cover makes this easier. The Sleep Foundation says washing the cover on its own, per its label, can prolong the life of the blanket inside.

Checking a beaded blanket over time

Seams take strain from the weight. Look over the pocket stitching when you wash the blanket, and stop using one that is leaking fill. Loose beads are small, so keep them away from young children and pets and vacuum up any that escape.

For other ways to keep a weighted blanket cool, see cooling weighted blankets. Our blankets section compares weighted, plush, knit and heated blankets side by side.