OET Writing Band Score: Grade B Path (350+)
What Grade B means in OET writing, how the 6 criteria translate into your score, and the specific errors that keep candidates stuck below 350.
After correcting more than 9,500 OET letters, one pattern is clearer than any other: most candidates who score below Grade B are not failing because of poor grammar. They are failing because they misunderstand the 6 assessment criteria — and specifically, which criteria cost the most marks.
350+
Score needed for Grade B
out of 500
6
Assessment criteria
all equally weighted
0–14
Scale per criterion
combined & scaled to 500
What Grade B (350+) Actually Means
OET Writing is scored on a scale of 0 to 500. Grade B requires a minimum of 350 out of 500.
Your score is not a simple average of six separate boxes. The 6 criteria are each assessed on a sub-scale, then combined and scaled. In practice this means:
- Consistent weakness on any single criterion can pull your total below 350, even if the other five are strong.
- A single catastrophic failure (completely misidentifying the purpose) affects multiple criteria simultaneously.
- There is no criterion you can ignore and still expect Grade B.
Common misconception
Candidates often believe OET Writing is primarily a language test. It is not. Language is one of 6 equal criteria. Candidates with C1-level grammar fail regularly because content selection and task fulfilment are the real differentiators.
The 6 Criteria: What Each One Costs You
Criterion 1: Purpose
What it assesses: Does your letter do what it is supposed to do?
This criterion catches letters that miss the point entirely. A grammatically perfect letter that fails to state its purpose will fail here.
| ❌ Fails this criterion | ✅ Meets this criterion |
|---|---|
| ”I am writing regarding Mrs. Chen." | "I am writing to refer Mrs. Chen for specialist cardiac assessment.” |
| Purpose buried in paragraph 3 | Purpose stated in the first 15 words |
| Letter type unclear to reader | Letter type immediately evident |
Grade B threshold: Purpose explicit in the opening sentence. Letter consistently serves the stated purpose from start to finish.
Criterion 2: Content
What it assesses: Did you select the right information from the case notes?
This is the criterion most candidates misunderstand. They read the case notes and copy them all — or summarise them all. Both approaches fail.
The content selection test
For every piece of case note information, ask: “Does the reader of THIS specific letter need this to make a clinical decision?”
Common over-inclusions
- • Full medication list when only 1–2 are relevant
- • Childhood diagnoses unrelated to current episode
- • Social history irrelevant to the reader’s role
- • Clinical abbreviations copied without expansion
What must always be included
- • The management plan (often the most critical)
- • Relevant current medications with doses
- • The clinical reason for writing
- • Any safety-critical information
Grade B threshold: All included content relevant. All critical information present. Nothing invented.
Criterion 3: Conciseness and Clarity
What it assesses: Is the letter focused without losing important information?
A 280-word letter that repeats itself scores lower than a 190-word letter that covers everything once, clearly.
Too short
Ideal
Too long
Grade B threshold: Each piece of information appears once. Sentences are clear and direct. No unnecessary repetition.
Criterion 4: Genre and Style
What it assesses: Does it sound like a real clinical letter?
| ❌ Wrong register | ✅ Correct register |
|---|---|
| ”The patient is doing better now." | "The patient’s condition has improved with current management." |
| "I humbly request your esteemed attention." | "I would be grateful for your assessment." |
| "She has a bad heart condition." | "She has a history of ischaemic heart disease.” |
Grade B threshold: Professional, clear, appropriate to the clinical context. Not casual, not artificially formal.
Criterion 5: Organisation and Layout
What it assesses: Is information structured logically?
Salutation
Dear Dr. [Name] or Dear [Title/Role]
Purpose statement
Why you are writing, for whom, and the clinical reason
Relevant background
Concise history — only what the reader needs
Current situation
Presenting complaint, findings, current condition
Action / request
What you are asking the reader to do — specific and clear
Professional closing
Closing sentence + signature
Criterion 6: Language
What it assesses: Grammar, vocabulary, spelling, punctuation.
This is the criterion most candidates over-focus on. Language matters — but it is rarely the primary reason for failing when the other five criteria are weak.
Most frequent language errors in failed letters
Why Candidates Fail Despite Good Grammar
The data from our 9,500+ corrections is consistent. Candidates who fail OET Writing score below 350 primarily because of criteria 1, 2, and 3:
- They write purpose-free openings
- They include everything from the case notes
- They repeat information across paragraphs
Grammar instruction alone does not solve these failures. Understanding the marking criteria — and practising with feedback from someone who applies those criteria — does.
”The most common pattern we see is candidates with strong grammar who still score below Grade B. They include too much information, miss the purpose, or misjudge the tone. These are the areas where human feedback makes the real difference.”
— Senior OET Corrector, Motivation Feedback (10+ years OET assessment experience)
How to Use This in Your Next Practice Letter
Before writing
Identify the purpose, the reader, and which case notes are relevant to that reader. Criteria 1 and 2 are decided before you write your first word.
While writing
Ask of each sentence: does it serve the reader? Is it adding new information or repeating something already said? Criteria 3 and 4 are built sentence by sentence.
After writing
Review paragraph flow, check grammar, verify your opening and closing are complete. Criteria 5 and 6 are confirmed in your review phase.
When you receive feedback, cross-reference each comment with the relevant criterion. Build a personal list of weak areas to target in your next practice letter.
The most efficient path to Grade B is honest, criterion-referenced assessment of your actual letters — not more self-study. Explore correction packages or start with a single letter assessed against all 6 official criteria and returned in 24–72 hours.
Frequently asked questions
Common questions on this topic — full answers below.
What score do I need for Grade B in OET Writing?
Why do candidates with strong English still fail OET Writing?
Which OET writing criterion costs candidates the most marks in 2026?
How is the 0–500 OET writing score calculated?
How many practice letters does it take to move from C+ to Grade B?
Does grammar matter most for Grade B?
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