Here's the thing: most students stuck at Band 5 for IELTS Writing Task 1 aren't making random mistakes. They're making the same five or six predictable errors, over and over, across every letter they write. And the best part? These mistakes are completely fixable. You just need to know what they are.
Band 5 is that frustrating middle ground. Your letter gets the job done. The examiner understands what you're asking for. But something feels off. Your grammar feels clunky. Your tone sounds weird. Your paragraphs don't flow. You're stuck because you can't see the pattern.
That's what this post is for. I'm going to show you exactly which mistakes keep students at Band 5, why examiners penalize them, and how to fix them before you submit. Whether you're using an IELTS writing checker or reviewing manually, these patterns are what separate Band 5 from Band 6 and above.
Let me be blunt: Band 5 is the "technically correct but unmistakably awkward" band. The IELTS band descriptors for Writing Task 1 look for four things: Task Response, Coherence & Cohesion, Lexical Resource, and Grammatical Range & Accuracy. Band 5 typically means you're hitting Task Response (you answered the question), but you're weak in the other three.
What does that look like in real terms? You write 150+ words. You include all the required information. You use a formal letter format. None of that is wrong. But your sentences are repetitive. Your transitions between paragraphs feel abrupt. Your word choices are safe and basic. Your grammar is correct but limited. You're not making mistakes; you're just playing it too safe, and examiners notice.
The good news: once you know what low-band patterns look like, you can spot them in your own writing and fix them before submission.
Band 5 writers follow predictable patterns. Recognizing these common IELTS letter writing errors is the first step to correction. Below are the six most damaging mistakes and how to fix them.
This is the number one Band 5 killer. You write too many sentences that follow the exact same pattern: subject + verb + object + period. Then repeat.
Weak (Band 5): "I am writing to you. I want to complain about my booking. I made a reservation. I paid 200 pounds. I arrived at the hotel. The room was not ready. I was very disappointed."
Notice how every sentence is the same length? Every one starts with "I"? That's Band 5. You're not making grammar mistakes, but you're not showing grammatical range either, and that tanks your Grammatical Range & Accuracy score.
Good (Band 7+): "I am writing to lodge a formal complaint regarding my recent booking at your establishment. Having paid 200 pounds for a confirmed reservation, I arrived to find that my room was not ready. This level of service fell significantly short of expectations."
See what changed? Different sentence lengths. A dependent clause at the start ("Having paid..."). A more sophisticated construction ("fell significantly short of" instead of "was not"). You're still being formal and clear, but you're showing flexibility with sentence structure.
Quick fix: As you write, count your sentences. If more than three in a row start with the same word or have the same length, stop. Deliberately change the next one. Use a dependent clause. Combine two short sentences. Break one long sentence into two. This single habit can lift you from Band 5 to Band 6 almost instantly.
Different IELTS Task 1 letters demand different tones. A complaint needs firmness with respect. A request for information needs politeness with clarity. A resignation letter needs professionalism with gratitude. Band 5 writers often use the wrong tone, and examiners dock marks for Task Response because the letter doesn't match the register the task asks for.
The most common problem? Being too casual in formal situations.
Weak (Band 5): "Hi there, I got your email about the job offer. Thanks so much for thinking of me. Unfortunately, I can't take the job because I'm moving to Spain. Maybe we can work together in the future. Cheers, James."
The content is fine. But this isn't a formal letter. It's what you'd send a friend. No greeting line. No proper closing. "Thanks so much" and "Cheers" are too informal for declining a job offer professionally.
Good (Band 7+): "Dear Mr. [Name], Thank you for your offer of employment. I am grateful for the opportunity you have presented to me. Unfortunately, I must decline due to my relocation to Spain. I hope we may have the opportunity to work together in the future. Yours sincerely, James"
Same information. Different tone. "I am grateful" instead of "Thanks so much." "I must decline" instead of "I can't take." Proper salutation and closing. This is appropriate for the situation. Our guide on formal letter tone and IELTS formal letter correction covers this in depth.
Quick fix: Before you write, identify what type of letter it is: complaint, request, application, explanation, or apology. Each has different tone rules. For complaints, be firm but not rude. For requests, be polite but direct. For apologies, take responsibility without over-explaining. Match your tone to the task, and your Task Response score jumps.
Your opening sentence tells the examiner what you're doing. Band 5 writers use vague openings that meander instead of stating purpose clearly. Your closing sentence is your last chance to leave an impression, and Band 5 writers often waste it.
Weak opening: "I am writing this letter because there is a problem with something that happened recently."
What's the problem? We don't know yet. This opening is too vague. It doesn't tell the examiner anything specific.
Good opening: "I am writing to lodge a formal complaint regarding the defective laptop I purchased from your company on 3rd September."
Now the examiner knows the letter type (complaint), the subject (defective laptop), and the company (yours). In one sentence, you've established context and purpose. That's coherence. If you want to go deeper, check out our post on letter opening strategies and formal register.
The same goes for closing sentences.
Weak closing: "I hope you will do something about this soon. Thank you for your time. I look forward to hearing from you."
These sentences are soft and generic. "Do something about this" is vague. The closing doesn't specify what action you want.
Good closing: "I expect either a replacement or a full refund within 14 days. Please contact me at your earliest convenience to arrange this. I await your prompt response."
Now you've restated what you want (replacement or refund), given a timeframe (14 days), and left the door open for contact. This is coherent and direct.
Band 5 writers often write one big paragraph or create paragraph breaks randomly, without following any logic. IELTS Task 1 letters need clear structure: introduction, body (one or more paragraphs), closing. Examiners look for Coherence & Cohesion, which includes how well you organize ideas across paragraphs.
Here's a typical Band 5 structure:
The body paragraph tries to do too much. You jump from reason A to reason B to a question to a condition, all without transitions. Examiners see this and mark you down for Coherence & Cohesion because they have to work to follow your logic.
Better structure looks like this:
Each paragraph has one main idea. Transitions between paragraphs are clear. The examiner doesn't have to hunt for your logic.
Quick fix: After you draft your letter, read it aloud. If you lose track of what you're talking about or why you just said something, your paragraph structure is weak. Reorganize so each paragraph has a clear topic sentence. That alone lifts Coherence & Cohesion scores.
This is a Lexical Resource issue. Band 5 writers use the same word three, four, or five times in a short letter because they don't have synonyms ready.
Weak: "I am writing about a problem with my booking. The problem is that the hotel is not good. The hotel said my booking was confirmed. The hotel did not have my booking. This is a big problem for me."
The word "booking" appears four times. "Problem" appears three times. "Hotel" appears three times. This isn't natural English, and it signals limited vocabulary to the examiner.
Good: "I am writing to report a discrepancy with my reservation. Although the establishment initially confirmed my booking, they subsequently informed me that no such reservation existed in their system. This error has caused me considerable inconvenience."
Look at the synonyms: "booking" becomes "reservation," then "booking" again (that's fine once more), then we drop the noun entirely. "Hotel" becomes "establishment." "Problem" becomes "discrepancy" then "error." This shows Lexical Resource strength.
Quick fix: Before you submit, highlight every noun and verb you use more than twice in one letter. For each repetition, ask: "Is there a synonym?" If yes, swap it. This takes two minutes and can boost your Lexical Resource score noticeably.
This isn't just style. IELTS examiners expect proper formal letter conventions. Missing or incorrect formatting costs you Task Response marks because you haven't met the task requirements.
Band 5 mistakes include:
The correct format for a formal IELTS Task 1 letter looks like this:
Semi-formal letters (to a friend or acquaintance you're writing professionally) can use "Dear [First name]" and "Best regards" or "Kind regards." But formal complaint and formal request letters need the structure above. Our guide on IELTS general training letter format and common mistakes walks through this with real examples.
Quick fix: Save a template. Before every practice letter, copy and paste the correct format. This ensures you never lose marks for missing structure. It takes 30 seconds and is marks-free improvement.
You now know what breaks Band 5 writers. Here's what to check before you submit any letter:
That's it. Seven checks. If you can say yes to all seven, you're no longer a Band 5 writer. You're heading toward Band 6 or 7.
Manually checking all seven of these points takes time and a trained eye. An IELTS writing checker speeds up the process. You write your letter, paste it into a free IELTS writing checker, and get instant feedback on sentence variety, tone, vocabulary repetition, and formatting. It catches Band 5 patterns before you even realize they're there, functioning like an IELTS essay checker but specifically designed for Task 1 letters.
Our IELTS writing checker analyzes your Task 1 letter for Band 5 patterns. Get instant feedback on sentence variety, tone, vocabulary, and structure.
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