Affect or Effect?

The Difference between "Affect" and "Effect"

"Affect" and "effect" are easy to confuse. "Affect" means to change. "Effect" means a result. Here is more detail:

• Affect. "Affect" means to change, to impact on, or to transform. For example:
• I want to affect the vote.

Notice that "affect" is written with "to" in front. This tells us that "affect" is a verb.

• Effect. "Effect" means a result, a consequence, or an appearance.
• Your work has an effect on the vote.

Notice that "effect" is written with "an" or "the" in front. This tells us that "effect" is a noun.

Top Tip

• Use "effect" if the word before is "an" or "the."

This tip works because "effect" is a noun, and only nouns can be preceded by articles (i.e., "a," "an," and "the"). Verbs can't.

(This top tip will see you right most of the time.)

A Video Summary

Here is a short video summarizing the difference between "affect" and "effect."

Ready for the Test?

Example Sentences with "Affect"

Remember that "to affect" is a verb meaning to change, to impact on, or to transform. For example:

• Did the cold affect you?
• Do not use low-fat milk. It will affect the taste.

Example Sentences with "Effect"

Remember that "effect" means result, outcome, consequence, or appearance. For example:

• What effect did your reprimand have?
• That is a nice effect.

A Little Trick To Spot "Effect"

The word "effect" has several meanings. It can mean "outcome," "consequence," or "appearance." Try using one of these instead of "effect." If the sentence still makes sense, then "effect" is almost certainly correct.

(This trick works because "effect" is a noun, just like the words "outcome," "consequence," and "appearance.")

A Little Trick To Spot "Affect"

Try using the verb "to transform" (in its various forms, e.g., "transforming," "transformed," "transforms") instead of "affect." If the sentence still makes sense, then "affect" is almost certainly correct. However, if you find yourself trying to use "transformation," then you should be using "effect" because both are nouns.

(This trick works because "to transform" is a verb, just like "to affect." )

Some More Example Sentences with "Effect" and "Affect"

Here are some more example sentences with "effect" and "affect":

Example 1:

• What effect did foot-and-mouth disease have on your business?
(The word "effect" is a noun.)

Top Tip

Try substituting the noun "effect" with the noun "consequence" to confirm that it's a noun.

Substitution Test: "What consequence did foot-and-mouth disease have on your business?"
(As this sounds okay, "effect" must be correct.)

Example 2:

• Did foot-and-mouth disease affect your business?
(The word "affect" is a verb.)

Top Tip

Try substituting the verb "affect" with the verb "transform" to confirm that it's a verb.

Substitution Test: "Did foot-and-mouth disease transform your business?"
(As this sounds okay, "affect" must be correct.)

Example 3:

• Do not allow this incident to effect your decision.

Top Tip

Do the substitution test.

Substitution Test: "Do not allow this incident to consequence your decision."
(As this is nonsense, "effect" must be wrong.)

The Other Substitution Test: "Do not allow this incident to transform your decision."
(As this sounds okay, "affect" must be correct.)

Note: Sometimes, the noun-substitution test won't work with "consequence" because "effect" is quite a versatile word. You might have to try other nouns, e.g., "appearance." If you find yourself trying to use this word as a verb (e.g., "appear," "appears"), then you should be using "affect" not "effect."

It's Not That Simple Unfortunately

Most of this page is dedicated to telling you that "effect" is a noun and "affect" is a verb. That is an appropriate start point for learning about the difference between "effect" and "affect," but unfortunately it is not always true. Be aware that "effect" can be a verb, and "affect" can be a noun.

The Verb "To Effect"

"To effect" as a verb is fairly rare, but it is useful in business writing. It means "to bring into being." For example:

• We will effect the new law on Monday.
• The new policy will be effected as soon as the paper is signed.

The Noun "Affect"

The noun "affect" is extremely rare. It is used in psychology to describe a subjective feeling caused by a thought or other stimulus. It is similar to mood or emotion and carries a connotation of there being external physical signs. For example:

• The patient displayed an unusual affect when questioned.