Margaret de Lowe (née Leigh; 1414 – 1454) was the 19th great-grandmother of Cometan, classified as one of Cometan’s medieval paternal ancestors in the Taylor family line.  

Along with her husband Geoffrey de Lowe (1410 – 1451), Margaret is one of the earliest known ancestors of Cometan. She is recorded as having been born in Lyme Handley (Lyme Park) in Cheshire and is known to have given birth to two daughters named Jane and Virginia and two sons named Lawrence and Thomas. Margaret is recorded as having died at the age of thirty-eight in Macclesfield in Cheshire. 

In Cometanic ancestry, Margaret is categorised as part of the 21st generation retrograde, and because she was born before 1453, she is classified as a medieval ancestor of Cometan, a title that is rarely bestowed.