IELTS Writing Punctuation: 9 Rules That Protect Your Band
Quick answer: Punctuation affects your IELTS Writing score through the Grammatical Range and Accuracy criterion, which is 25% of your band. The band descriptors mention punctuation directly: Band 7 requires good control with only a few errors, Band 6 allows some errors, and Band 5 says punctuation may be faulty. The nine rules below cover almost every error examiners see, and a 3-minute check at the end of each task catches most of them.↗ Share on X
Punctuation improves your IELTS Writing band score because it is assessed inside Grammatical Range and Accuracy, one of the four criteria that each count for 25% of your mark. The public band descriptors name it directly. At Band 7 the examiner expects "good control of grammar and punctuation" with only a few errors. At Band 6 there are "some errors in grammar and punctuation." At Band 5 punctuation "may be faulty." So a candidate whose grammar is Band 7 but whose commas and full stops are a mess can be held at Band 6 on that criterion. The good news: there are only about nine rules that matter, and they are learnable in a week.
Which punctuation errors cost the most marks?
IELTS Task 2 Complex Sentences: 7 Patterns for Band 8 →
IELTS Task 2 Body Paragraphs: A 4-Step Plan for Band 8 →
How to Stop Translating in Your Head in IELTS Speaking →Examiners are not hunting for exotic semicolons. They are reacting to errors that make sentences hard to read. In rough order of damage:
1. Comma splices: two full sentences joined with only a comma.
2. Run-on sentences: two full sentences joined with nothing at all.
3. Missing commas after linking words and introductory phrases.
4. Sentence fragments that start with a capital and end with a full stop but have no main verb.
5. Apostrophe errors, especially *its* versus *it's*.
6. Random capital letters on common nouns.
7. Missing full stops at the end of a paragraph.
The first two are the serious ones. Each of them turns two correct sentences into one incorrect sentence, which the examiner counts as an error in sentence structure, not just punctuation.
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Rule 1: Never join two sentences with only a comma
This is the comma splice, and it is the most common punctuation error in Band 6 and Band 6.5 scripts.
Wrong: *Many people prefer to live in cities, they offer more job opportunities.*
You have four correct ways to fix it:
| Fix | Example |
|---|---|
| Full stop | Many people prefer to live in cities. They offer more job opportunities. |
| Semicolon | Many people prefer to live in cities; they offer more job opportunities. |
| Comma + conjunction (and, but, so, because) | Many people prefer to live in cities because they offer more job opportunities. |
| Linking word after a full stop or semicolon | Many people prefer to live in cities. This is because they offer more job opportunities. |
The simplest fix is always the full stop. Short, correct sentences score higher than long, incorrect ones.
Rule 2: Comma after a linking word that starts a sentence
IELTS Task 2 Examples: 4 Types That Make Your Ideas Score →
IELTS Speaking: Fix Fluency Without Breaking Your Grammar →
IELTS Task 2 Examples: The 4-Step Formula That Lifts Scores →*However*, *Therefore*, *Moreover*, *In addition*, *For example*, *On the other hand*, *As a result*: all of these take a comma when they begin a sentence.
Wrong: *However the government has not acted.*
Right: *However, the government has not acted.*
The same applies to any introductory phrase of more than two or three words: *In many developing countries, access to clean water is limited.*
One warning: *however* in the middle of a sentence is not a conjunction. *The plan is cheap, however it is slow* is a comma splice. Write *The plan is cheap. However, it is slow* or *The plan is cheap, but it is slow.*
Rule 3: Comma before *and* or *but* only between sentences
Right: *The city built new roads, and traffic improved.* (two full sentences)
Right: *The city built new roads and widened the bridge.* (one subject, two verbs, no comma)
This rule separates Band 7 writers from Band 6 writers more than any other. Over-using commas before *and* is just as noticeable as missing them.
Rule 4: Do not put a comma between a subject and its verb
Wrong: *Students who study abroad, often become more independent.*
Right: *Students who study abroad often become more independent.*
Long subjects tempt you to pause with a comma. Resist it. If the sentence needs a pause, it probably needs to be two sentences.
Rule 5: Semicolons only between two full sentences
A semicolon is a soft full stop. Both sides must be able to stand alone.
Right: *Public transport reduces pollution; it also lowers household costs.*
Wrong: *Public transport reduces pollution; and lowers costs.*
If you are not confident, use a full stop instead. The semicolon adds nothing to your band if you use it badly, and it costs you nothing to avoid it.
Rule 6: Use a colon to introduce a list or an explanation
Right: *Three factors drive migration: work, education, and safety.*
Right: *The result was predictable: house prices rose.*
The part before the colon must be a complete sentence. *Three factors are: work, education, and safety* is wrong because *Three factors are* cannot stand alone.
Rule 7: Get the apostrophe right in *its* and *it's*
*It's* always means *it is* or *it has*. *Its* means *belonging to it*.
Right: *The company increased its profits.*
Right: *It's clear that the policy failed.*
For plural possession, the apostrophe goes after the *s*: *the students' results* (many students), *the student's result* (one student). Never use an apostrophe for a simple plural: *1990's* and *car's* for *cars* are errors.
Rule 8: Capitalize names and places, nothing else
Common nouns stay lowercase even when they feel important: *government*, *education*, *the internet*, *economy*, *university*. Capitalize *English*, *Japan*, *the United Nations*, *Monday*.
Random capitals on *Technology* or *Environment* are a weak-writer signal that examiners notice immediately.
Rule 9: No exclamation marks, ellipses, or emoticons
IELTS Writing Task 2 is formal academic writing, and Task 1 is formal reporting. There is no sentence in either task that needs an exclamation mark. An ellipsis (...) signals that you did not finish a thought. Question marks are acceptable only in a genuine rhetorical question, and one per essay is already a lot.
How does punctuation interact with the other criteria?
Good punctuation does more than protect your Grammatical Range and Accuracy score.
- Coherence and Cohesion improves when each sentence has a clear beginning and end. Run-on sentences make paragraphs feel disorganized even when the ideas are good.
- Task Response is easier for the examiner to follow when your main point in each paragraph is one clean sentence.
- Lexical Resource is not directly affected, but a misplaced apostrophe in a strong word (*the governments' responsibility* when you meant one government) can change the meaning.
In other words, punctuation is cheap to fix and pays in more than one place.
A 3-minute punctuation check for the end of each task
Leave three minutes at the end of Task 2 and two minutes at the end of Task 1. Do this, in order:
1. Read every sentence that contains a comma and ask: are there two full sentences on either side of it? If yes, change the comma to a full stop.
2. Scan for linking words at sentence starts (*However*, *Therefore*, *In addition*). Each needs a comma after it.
3. Find every *it's* and check it means *it is*. Find every *its* and check it shows possession.
4. Look at capital letters in the middle of sentences. Keep names and places. Lowercase the rest.
5. Check the last sentence of each paragraph ends with a full stop. Candidates often forget it when they are rushing to the next paragraph.
With practice this takes less than three minutes, and it typically removes the few errors that separate Band 6.5 from Band 7 in Grammatical Range and Accuracy.
Practice drill: 10 sentences a day
Write ten sentences each day for a week, each one using a different structure: a compound sentence with *and*, one with *but*, one starting with *However*, one with a semicolon, one with a colon and a list, one with a relative clause (*which*, *who*), one with *its*, one with *it's*, one with a plural possessive, and one long sentence that you then split into two. Check them against the rules above. By day seven the rules will feel automatic, which is the only state that survives exam pressure.
Your next step
Take the last Task 2 essay you wrote and highlight every comma. For each one, ask whether the words on both sides could be two separate sentences. Count how many comma splices you find. If it is more than two in a 270-word essay, make Rule 1 your only focus for the next three practice essays before you move on to the rest of the list.
FAQ
Does punctuation really change my IELTS Writing band score?
Yes. It is assessed under Grammatical Range and Accuracy, worth 25% of your Writing score, and the band descriptors mention punctuation explicitly from Band 5 to Band 7. Frequent comma splices can hold an otherwise Band 7 script at Band 6 on that criterion.
Should I use semicolons in IELTS Writing to show range?
Only if you are sure both sides are full sentences. A correct semicolon helps a little; an incorrect one is counted as an error. A full stop is always a safe replacement.
What is the single most common punctuation mistake in IELTS essays?
The comma splice: joining two complete sentences with only a comma, often around words like 'however' or 'therefore'. Fix it with a full stop, a semicolon, or a comma plus a conjunction such as 'and', 'but', or 'because'.