Oversized Blankets

No matter the size of bed you have, an oversized blanket allows for shrinkage as a result of washing without losing its fitting across your mattress. Now this doesn’t mean that if you have a single or double bed that you should buy a King size sheet to cover your bed with. A good rule of thumb would be to buy “one-up” from the size you need. For example, if you have a single bed, then get a double bed blanket. This way, shrinkage will have no, or very little, effect. This of course, does not apply to fitted sheets as they are another story entirely.
Oversized Blankets:

Oversized Blankets example. Pictured: Creswick Luxurious All-Natural 100-Percent Australian Merino Wool Oversized Blanket, Full/Queen Size, Sahara by Creswick Australian Mills