Grammar
Comma Splices: The Most Common Punctuation Mistake
What a comma splice is, why it weakens sentences, and four clean ways to fix one.
By Vocabaura Editorial · Published 13 August 2026 · 4 min read
Quick answer
A comma splice joins two complete sentences with only a comma. Fix it with a full stop, a semicolon, a joining word like and or because, or by rewriting one half as a dependent clause.
A comma splice is the sentence equivalent of taping two objects together and hoping nobody leans on them. It happens when two independent clauses, each able to stand alone as a sentence, are joined by a comma with nothing else holding them.
How to Spot One
Cover the comma. Read what’s on each side. If both halves could end with a full stop on their own, you have a splice.
Comma splice
The deadline moved, we had to rewrite the plan.
Fix 1: full stop
The deadline moved. We had to rewrite the plan.
Fix 2: semicolon
The deadline moved; we had to rewrite the plan.
Fix 3: conjunction
The deadline moved, so we had to rewrite the plan.
Fix 4: subordinate
Because the deadline moved, we had to rewrite the plan.
Which Fix to Choose
| Fix | Effect | Best for |
|---|---|---|
| Full stop | Clean separation | Emphasis, plain style |
| Semicolon | Close link, formal | Two balanced ideas |
| Comma + and/but/so | Natural flow | Most everyday writing |
| Subordinate clause | Shows cause or order | Explaining why something happened |
The Words That Trap Writers
However, therefore, moreover and nevertheless are adverbs, not conjunctions. They cannot join two sentences with a comma. “It rained, however we continued” is a splice; write “It rained; however, we continued” or start a new sentence.