Quick answer: Affect is usually a verb meaning to influence (the weather affects my mood). Effect is usually a noun meaning a result (the medicine had a strong effect).
Affect = action
Use “affect” when something is acting on something else: “Lack of sleep can affect your memory.”
Effect = end result
Use “effect” for the result or outcome: “The new rules had no effect.” It often follows words like “the”, “an”, “any” or “no”.
Examples
| Incorrect | Correct |
|---|---|
| The noise effected my sleep. | The noise affected my sleep. |
| It had a big affect on me. | It had a big effect on me. |
| Side affects | Side effects |
The exceptions
- Effect as a verb means to bring about: “They worked to effect change.”
- Affect as a noun is a psychology term for visible emotion: “The patient had a flat affect.”
Memory trick
Remember RAVEN: Remember, Affect is a Verb, Effect is a Noun.
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Frequently asked questions
Is it “affected” or “effected”?
Usually “affected”, meaning influenced: “Thousands were affected by the storm.”
Is it “side affects” or “side effects”?
“Side effects”, because it is a noun meaning results.
What does “effect change” mean?
To bring about change. This is one of the few times “effect” is a verb.