Willson
A spelling variant of Wilson meaning “son of Will,” with Will being a short form of William.
The #3,679 most common surname in the United States (2010 Census) — about 1 in every 31,965 Americans shares it.
Etymology
Willson is an English patronymic surname built from the medieval pet form Will, short for William, plus son. The literal sense is therefore “son of Will” or “son of William.” It is essentially a spelling variant of the far more common Wilson.
History
The surname appears in English records as a variant spelling rather than a separate origin, and historical surname dictionaries routinely cross-reference it under Wilson. It was especially associated with English regional usage, and one late-19th-century source notes it as a rare form in Huntingdonshire and Cambridgeshire. In the modern era it survives, but much less commonly than Wilson.
Origin
Regions
Variant spellings
Fun fact
Some surname compilers treated Willson simply as one of several spelling shapes under the wider Wilson family, rather than as a distinct surname.
From the historical record
“Wl WILLSON, Will's Son: v. WilP,^ Cp. Wilson. WILLY = Willey, q.v. WILLYAMS = Williams, q.v. WILMAN: v. Willman. LLlHIRE}f°'^Wi't^'^"'«''l-^-”
— Surnames of the United Kingdom: a concise etymological dictionary (2 vols in 1)