When thinking about matching the tartan between the kilt and day plaid remember what you are going to use it for. It is a ground cloth, a lap blanket, shaw and other uses to keep you warm. These uses will increase the chance that this will get dirty quickly. J. Charles Thompson, in "So you're going to wear the kilt" describes the day plaid as "double width (52 to 56 inches) and three and a half yards long. It is fringed at both ends." At $75-$80 a yard that $250 - $300 I would be putting on the ground. I'll find an inexpensive tartan blanket that is a lot cheaper. The tartans may not match but if I;m sitting on it who will know.