Mr. vs. Mr Formatting
Mr. versus Mr is primarily a regional and house-style formatting choice. Chicago uses the period-ending form, while Cambridge’s British entry presents Mr without a period, so consistency with the chosen style matters.
Both “Mr.” and “Mr” are established style forms. Chicago uses “Mr.”; Cambridge’s British entry uses “Mr” without a period.
Key details
Important caveats
Regional Form
Cambridge’s British-facing dictionary entry presents “Mr” without a period.
Style Boundary
Follow the document’s regional or house style consistently rather than treating one established form as universal grammar.
Further guidance
Chicago Form
Chicago style examples use “Mr.” with a period.
Practical Application
Choose “Mr.” or “Mr” according to the governing regional/house style and apply that choice consistently alongside comparable honorifics. Do not “correct” a document from one established style to the other without a style reason.
Reader Check
Is the document following a style that retains periods in abbreviated titles, or one that normally omits them for forms such as “Mr”?
Worked Example
A Chicago-style document may use “Mr. Patel,” while a British-style document may use “Mr Patel.” The important editorial decision is to follow the selected system consistently.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- MR — Cambridge Dictionary (opens in a new tab)Cambridge University Press · Documents British-style Mr as a title before a man’s name
- Chicago Q&A — abbreviations such as Mr. and Dr. (opens in a new tab)The Chicago Manual of Style / University of Chicago Press · Chicago examples use period-ending Mr. and Dr. and treat them as familiar title abbreviations