It is difficult to find the actual measurement for many bedspreads even when you have the package in hand. Overstock.com does list exact sizes under product details when you click on Show More. I have bought bedding and other items over the years, and have always been pleased with the quality and shipping.

The word "bedspread" has virtually disappeared from bedding vernacular. About the largest you will find in a COVERLET is 98 x 114. A duvet cover, same thing. A comforter, same thing, None of these were designed to cover the area beneath your sleeping pillows!

Assuming a nine inch box spring, and a 20 inch mattress? You'd be better off with a LOW PROFILE set of box springs. These are relatively VERY inexpensive.... less than making a custom cover, which is also possible, But,,,,,,,with a four inch box?? You can cover with 108 inches in width and length will be no issue either. You will have TONS from which to select. Here's one at 114"!!

https://www.thecompanystore.com/quilts-coverlets/putnam-matelasse-floral-cotton-coverlet/50170-ps-c18.html

Change the box springs......: ) Make CERTAIN you can fold or buy split. Doorways and stair surprise not needed, right? Overstock below link Or simply visit a local mattress brick and mortar.

https://www.overstock.com/Home-Garden/Priage-4-inch-Split-King-size-Low-Profile-Bifold-Folding-Mattress-Foundation/12226259/product.html?kwds=&option=19655797&refccid=FEB5IWYH6TSLU62AVH3ZROWNEE&rfmt=size%3AKing%7Cother%20types%3ABox%20Spring%20Only&searchidx=10

!20 x 120 will not exist, ...ANYWHERE EXCEPT IN A CUSTOM COVER . You can have it made, it will have seams

This bedspread is 120x120:

https://www.wayfair.com/bed-bath/pdp/august-grove-orben-bedspread-set-w000525209.html?piid=927073380%2C927073387

There may be others here, I only looked at the one above:

https://www.wayfair.com/keyword.php?keyword=120x120+king+bedspread

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120x118 bedspreads:

https://www.bedbathandbeyond.com/store/product/510-design-oakley-bedspread-set/5257436?keyword=120-x-120-bedspread&size=CAL-KING

https://www.target.com/p/glen-reversible-bedspread-set/-/A-77419034?preselect=76628379#lnk=sametab

This is listed as the 120 by 120 at Macy's.

https://www.macys.com/shop/product/madison-park-quebec-quilted-bedspread-sets?ID=11171525&CategoryID=60241&sizes=BED_AND_BATH_TYPE!!Bedspreads&swatchColor=Dark%20Gray#fn=SIZE%3DTEXTILES_BED_SIZE%3AKing

These were SUPER helpful - thank you all so much for your help! I decided to swap out my standard box spring with a low-profile box sping and it opened up a ton more options for top bedding. I wasn't aware those existed and am so pumped for the simple and cost-friendly solution.

Thanks again!