Difference Between That and Which (with Examples and Comparison Chart)

Clause implies a set of words which is a part of a sentence, but it contains its own subject and predicate. A relative clause is a type of clause which expresses the person or thing, the speaker is referring to. Basically, we use who, whose, whom, that and which, in relative clauses. Many people suffer dilemma in using that and which in the sentences. While that is used to talk about things and sometimes about people, which is used to discuss things only.

Let’s take a look at the example to understand their difference:

An Atlas is a book that contains maps or charts.
Finally, we travelled to all the places, which you suggested.

In the given sentences, you might have noticed that while which is preceded by a comma, but there is no such comma in case of that. In simple words, ‘that’ adds essential information to the sentence, but ‘which’ adds supplementary information to the sentence.

Comparison Chart

Basis for Comparison	That	Which
Meaning	That is normally used to point out a person or an object, distant to the speaker, or add a clause which enhance the meaning of subject.	Which is a wh-word, which is used to ask questions or add some information to the preceding noun, which is not pertinent to the subject.
Part of speech	Pronoun, determiner, adverb, conjunction	Pronoun and determiner
Clause	It is used with restrictive relative clauses.	It is used with non-restrictive relative clauses.
Refers to	People or things	Things only
Example	Paul called me on the number that was out of service.	The train runs to Nagpur, which is its last destination.
Example	The man who is standing at the door that's my father.	She went to the village, which is situated near the river.

Definition of That

‘That’ is a relative pronoun which identifies a particular person or thing, referred by the speaker. It is commonly used with singular nouns.

When writing sentences with relative clauses, we use ‘that’ to provide further information, which elucidates the antecedent in the main clause. Now we’ll discuss how to use that in our sentences:

As a determiner, it is used to address a person or thing which is not in contact with the speaker:
- Elly sold that house in which she used to live in New York.
- I was talking about that lady wearing the pink dress at the event.
As a determiner, it can also be used to refer to something which is previously mentioned, to imply a comparison:
- Here is the pen that you are looking for.
- These spectacles are better than that.
As an adverb, it is used to talk about degree or extent:
- The medicine is not that important for me.
- He is not that lucky for me.
As a conjunction, it introduces a clause which expresses additional information about the subject:
- It was raining heavily that I couldn’t reach the exam centre on time.
- She doesn’t like the movies that are not interesting.
- Maria accepted that it was her fault.

Definition of Which

Which is an interrogative pronoun, i.e. a wh-word that is used for asking the question, or seeking information concerning one or more people or objects from a given set.

Further, ‘which’ is also used to refer to something which is already specified to institute a clause for providing additional information incidental to the main clause. Now, let’s take a look at the points given below, to understand its uses:

It is used to ask questions wherein there is a specified set of answers:
- Which is your house?
- Which book is mine?
It is also used to decide among various options:
- Which footwear should I buy?
- Which dress would you like to wear to the party?
It is also used to add specific information to the main clause, which is succeeded by a comma:
- Pankhuri got selected in IIT, which surprised all her group members.
- Today’s weather is great for a long drive, which is our favourite thing.
- Last year we went to Agra to see the Taj Mahal, which we’re longing for years.

Key Differences Between That and Which

The difference between that and which can be drawn clearly on the following grounds:

‘That’ is a pronoun, which is mainly used to point out something or someone, not in direct contact with the speaker. It may also be used to add a clause to the main clause, so as to enhance its meaning. As against, ‘which’ is an interrogative pronoun that can be used to ask questions that have limited or fixed answer. It can also be used to add a clause which only adds information but is not relevant to the main clause.
While ‘that’ can be used as a pronoun, determiner, conjunction and adverb, which can be used only as a pronoun and determiner.
When it comes to usage, that is used to institute an essential/restrictive clause. An essential clause is one that adds some information that is important with respect to the subject of the sentence. On the other hand, a non-essential/non-restrictive clause is introduced by ‘which’, i.e. it only adds supplementary or incidental information.
We use ‘that’ to refer to people or things, whereas we use ‘which’ to refer to things only.

Examples

That

Sam works for an NGO that operates in Delhi.
What’s wrong with the vehicle that you bought last year?
It is a heart touching movie that can make you cry.

Which

The Chief Minister started a fixed deposit for girls, which are below 12 years.
The car, which was stuck in the pothole, was sent to the service station.
The building collapsed due to the earthquake, which was recently built.

How to remember the difference

The best way to understand the difference between that and which is to use “parenthesis”. If the sentence is complete without parenthesis, you can use ‘which’, but if it is not, then use ‘that’.