Small quantities of patterns with other prefixes have been recorded but with little information and examples it is difficult to know how extensive these ranges were. They include:
C - five numbers known (C133, C511, C583, C655 and C1640)
F - three numbers known (F104, F113 and F131), both seen on William Kent figures. The 'F' may simply signify a figure.
K - one number known (K2059), on a 1950s stoneware casserole dish.
M - one number known (M1481) on a 1950s plate which exists as a boxed set with a small, matching ceramic-handled knife.
T - one number known (T225/5), on a square tile. The 'T' may simply signify a tile.
Y - one number known (Y9339), vine resist pattern on a yellow ground. A9339 is the same pattern on a white ground, so 'Y' may signify yellow.