William Nigel Paul Cash, usually Bill Cash (born 1940) is an English Tory politician, member of Parliament and opposition front-bencher.

He entered Parliament in 1984, when he became MP for Stafford in a by-election, and has served on various committees. He is known as a strong eurosceptic and at one point was ringleader of a rebellion over the Maastricht treaty that almost brought down John Major's government.

After he became leader, fellow rebel Iain Duncan Smith gave him the post of shadow Attorney General in 2001, and in 2003 was made a spokesman on Constitutional Affairs.