Here's what separates a Band 6 letter from a Band 7 letter: tone consistency. Not vocabulary. Not length. Tone.
Most Band 6 students make the same mistake. They'll write one sentence that sounds formal, then slip into casual language two sentences later. They mix "Dear Sir or Madam" with "Thanks a lot, mate." Examiners catch it immediately. When your tone doesn't match your letter type, Task Response drops from 7 to 6 right away.
This guide shows you exactly how to audit your letter tone before you submit. You'll learn the specific differences between Band 6 and Band 7 tone choices, see real examples of tone mistakes, and get a checklist you can use on every formal, informal, and semi-formal letter.
The IELTS examiner spends maybe 2-3 minutes reading your entire Writing Task 1. They're not reading for pleasure. They're checking one thing first: did you understand the register required by this letter type?
The IELTS band descriptors for Task Response explicitly say "appropriately addresses all parts of the task". That word "appropriately" means your tone has to fit the situation. A Band 7 response does this consistently. A Band 6 response does it, but with lapses.
Here's how examiners score Task 1:
Tone problems hit your Task Response score immediately. They also drag down Lexical Resource because you're mixing registers. That's a double penalty, and it's where most Band 6 students lose points.
IELTS Task 1 gives you one of three letter types: formal, semi-formal, or informal. Each has its own tone zone. Know your zone, stay in it.
Formal letters go to organizations, government bodies, or people you don't know. Your tone is respectful, professional, and distant.
Band 7 (Good): "I am writing to lodge a complaint regarding the faulty equipment I purchased on 15th July. I would appreciate your prompt attention to this matter."
Band 6 (Weak): "I'm really annoyed about the broken thing I bought last week. Can you guys fix this ASAP? It's seriously not cool."
The Band 7 version uses passive constructions ("I am writing"), specific dates, and indirect requests ("I would appreciate"). It keeps emotional language neutral. The Band 6 version uses contractions, vague references, slang ("not cool"), and exclamation marks. Band 6 students often swing too far informal in formal letters.
Semi-formal is where Band 6 students get stuck most often. You're friendly but still professional. You can use "I" and active voice, but you avoid slang and text-speak openings.
Band 7 (Good): "I wanted to reach out regarding the upcoming team retreat. Would you be able to accommodate my dietary requirements?"
Band 6 (Weak): "Hey! Just checking in about the retreat thing. Can you make sure there's vegan food for me? Cheers!"
Band 7 sounds warm but measured. Band 6 reads like a text message. Semi-formal means you drop the ceremonial distance, but you keep the structure intact.
Informal letters let you be yourself. You can use contractions, casual phrases, and some personality. But Band 7 informal isn't just "write like you text".
Band 7 (Good): "It's been ages since we last caught up! I'd love to hear what you've been up to. By the way, I'm planning a trip next month and would really enjoy seeing you if you're free."
Band 6 (Weak): "Yo! Haven't talked to u in forever lol. U coming to my thing next month??? Hit me up!!!"
Band 7 informal is still a letter. You vary sentence length, use punctuation correctly, and structure your ideas. You're just less formal. Band 6 informal sometimes dips into texting conventions (no capitals, abbreviations like "u"), which examiners mark as not meeting the formality standards of written communication.
You know what happens in most Band 6 letters? Tone shifts. Mid-letter. Without warning.
Here's an actual IELTS Task 1 prompt: "You lost an important document at a conference. Write to the organizers asking them to help you find it. Write at least 150 words."
This is formal. You don't know the organizers personally. Here's how a Band 6 student typically messes it up:
Band 6 (Tone all over the place): "I am writing to inform you of a serious situation that occurred at your conference last week. I lost a blue folder containing important documents. It's got my research notes in it and honestly I'm pretty stressed about losing it. Could you maybe check the lost and found? I would be eternally grateful if you could assist me. Thanks for your help, mate."
See the problem? "I am writing to inform you" sounds formal. Then "It's got my research notes" is casual. "Eternally grateful" is overly formal. "Thanks, mate" is way too informal. The tone bounces everywhere.
Here's what Band 7 consistency looks like:
Band 7 (Consistent tone): "I am writing to request your assistance in locating a document I misplaced during your conference last week. The document is a blue folder containing my research notes and is of considerable importance to my work. I would be grateful if you could check your lost and found facility or alert your staff. Thank you for your attention to this matter. I look forward to hearing from you."
Formal language throughout. "I am writing", "misplaced", "of considerable importance", "I would be grateful", "Thank you for your attention". No slips. No "mate". No exclamation marks. No contractions. That consistency is what pushes you from 6 to 7 in Task Response.
Quick fix: After you write your letter, go through it once looking only at tone. Highlight every contraction, casual phrase, and informal word. Count them. For formal letters, aim for zero. For semi-formal, keep it to one or two maximum. For informal, consistency matters more than word choice.
Some words are tone landmines. Use them wrong and you signal to the examiner that you don't understand register.
The Band 7 test: could an examiner tell what type of letter this is just by reading the first and last sentences? If yes, your tone is probably consistent.
Semi-formal is harder than formal or informal because the rules are fuzzy. Band 6 students struggle here most.
Task prompt: "Your manager has asked you to organize an office team building event. Write a letter to a local activity center asking for details about their facilities and pricing."
Semi-formal. You know the manager. It's work-related but not to a stranger.
Band 6 attempt: "Dear Sir, I am writing to inquire about your team building activities for our office. We need something fun and engaging for around 25 people. Can you tell me what you've got available? And how much does it cost? I'd really appreciate your quick response. Cheers, [Name]"
This letter can't decide what it is. "Dear Sir" is formal, but the rest is casual. "I'd really appreciate" is informal. "Cheers" is very casual. It reads like someone who doesn't know the register rules.
Band 7 attempt: "Dear [Name/Manager], I hope this finds you well. I'm reaching out to discuss team building options for our upcoming office event. We have approximately 25 participants and are looking for an engaging activity. Could you please provide details about your available programs and pricing? I'd appreciate a response at your earliest convenience. Best regards, [Name]"
Consistently semi-formal. "I hope this finds you well" signals friendly professionalism. "Could you please" is polite without being stiff. "At your earliest convenience" shows respect without sounding distant. "Best regards" is professional yet warm. The tone stays in zone throughout.
After you write your letter, run through this before you submit:
Do this check in 3-4 minutes. It catches 80% of tone inconsistency problems before you hit submit.
These mistakes come up constantly in Band 6 letters:
Band 6: "I am writing to complain about your service! It was terrible!"
Band 7: "I am writing to lodge a formal complaint about your service. The standard was unsatisfactory."
Exclamation marks make you sound emotional, not professional. In formal letters, emotion belongs in your word choice, not punctuation.
Band 6: "I'm so sorry to bother you, but could you maybe help me?"
Band 7: "I would appreciate your assistance with this matter."
Formal letters don't apologize for making requests. That weakens your position. State your need clearly and professionally.
Band 6: "I was wondering if maybe you could possibly send me information?"
Band 7: "Please send me information regarding your available programs."
Band 7 is direct. Band 6 sounds uncertain. Formal tone is confident tone.
Band 6: "I'm asking you to help me out because you're really good at this stuff."
Band 7: "I am requesting your assistance due to your expertise in this field."
Band 7 removes the informal "you" and replaces it with a more formal construction.
Band 6: "By the way, I noticed your team is awesome, so I thought you guys might be able to help?"
Band 7: "I believe your team's expertise would be valuable for our requirements."
Semi-formal isn't an excuse to be too casual. There's still a professional relationship at play.
One more thing separates Band 6 from Band 7: paragraph-level consistency.
Your opening paragraph sets the tone. Your body paragraphs maintain it. Your closing reinforces it. If paragraph 1 sounds formal, paragraph 2 semi-formal, and paragraph 3 informal, examiners notice immediately.
IELTS Task 1 letters are usually 3-4 paragraphs. Here's what Band 7 consistency looks like:
Formal letter structure:
Para 1 (Opening): "I am writing to..."
Para 2-3 (Details): Specific information, polite requests, professional tone
Para 4 (Closing): "Thank you for your attention to this matter. I await your response."
Every paragraph uses formal language. No slips. No casual shifts.
A Band 6 student might do this:
Para 1 (formal): "I am writing to inquire about..."
Para 2 (casual): "I really need to know about your stuff because I'm in a tough spot..."
Para 3 (formal again): "I would be grateful for your assistance..."
Para 4 (informal): "Cheers and thanks a lot!"
The tone bounces around. That inconsistency costs you points in Task Response and Coherence and Cohesion because it shows you can't sustain register control for an entire letter. If you want to see how this applies specifically to complaint letters, our guide on formal complaint tone breaks down exactly what Band 7 complaint letters look like.
Quick tip: When you finish your letter, read each paragraph independently. Does it sound like it was written by the same person in the same tone? If one paragraph feels "off", rewrite it to match the others.
You've written your 150-word letter. You have 7 minutes left. Use them strategically:
Minute 1: Read the task prompt again. Confirm the letter type in your head.
Minutes 2-3: Read your opening sentence and closing sentence back-to-back. Do they match in tone? If not, rewrite the closing.
Minutes 4-5: Scan for contractions, exclamation marks, and casual words. Mark each one.
Minutes 6-7: Fix the marked problems. Formal letter? Remove contractions and replace casual words. Informal letter? Make sure it's consistently conversational, not randomly formal.
This isn't deep revision. It's tone enforcement. It catches the mistakes that cost you band points. Use our free IELTS writing checker to catch tone issues you might miss manually.
Use our IELTS writing checker to analyze your letter for tone consistency, register appropriateness, and get a band score prediction. See exactly where tone slips happen and how to fix them.
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