Period After Yes or No When Followed by a Conjunction
The Period
Rulebase Summary
When the words after 'yes' or 'no' begin with a coordinate conjunction like 'and' or 'but,' or a subordinate conjunction like 'because' or 'though,' use a period after the 'yes' or 'no.' The conjunction signals a new, separate thought — the words are not simply echoing or confirming the question.
BGGP Period.17 · p.75 BGGP Yes and No.6 · p.426 BGGP Yes and No.7 · p.427
Examples
✗
A. Yes, and he was holding a firearm at the time.
✓
A. Yes. And he was holding a firearm at the time.
Conjunction after yes/no signals a new thought — period.
✗
A. No, but I saw her vehicle parked outside.
✓
A. No. But I saw her vehicle parked outside.
"But" starts a new independent thought after "No."
Style Guide References (3)
BGGP
Period.17
Page 75
BGGP
Yes and No.6
Page 426
BGGP
Yes and No.7
Page 427