| Barony Grimston of Westbury | |
| Creation Date: | 1964 |
| Remainder To: | 1st Baron's heirs male of the body lawfully begotten |
| Status: | Extant |
| Motto: | Mediocria Firma (Moderate things are stable) |
Baron Grimston of Westbury, of Westbury in the County of Wiltshire, is a title in the Peerage of the United Kingdom. It was created in 1964 for the Conservative politician and former Deputy Speaker of the House of Commons, Sir Robert Grimston, 1st Baronet. He had already been created a baronet in 1952. Grimston was the son of Reverend Canon the Hon. Robert Grimston, third son of James Grimston, 2nd Earl of Verulam. the titles are held by his grandson, the third Baron, who succeeded his father in 2003.
The barony of Grimston of Westbury was one of the last hereditary baronies created in the Peerage of the United Kingdom.
The heir presumptive is the present holder's brother the Hon. Gerald Charles Walter Grimston (b. 1953)
The heir presumptive’s heir apparent is his son, Edward Charles Luckyn Grimston (b.1985)