You're staring at a General Training letter prompt. The instructions say "write a letter to your friend about a recent holiday." You nail the first draft. Then three minutes later, you see another one: "write a letter to the manager of a restaurant complaining about poor service." Same format. Completely different tone. Completely different result.
Here's the thing most students miss: you can nail the structure and vocabulary but still lose band points because you misjudged the tone. You'll write casually to a hotel manager or sound robotic to a mate. The IELTS examiners reward writers who match tone to context. That's non-negotiable for Band 7+.
This guide teaches you how to recognize when a letter needs formal tone, when it needs informal tone, and how to catch yourself getting it wrong before you submit. Use our IELTS writing checker to verify your letter's tone matches the prompt.
Task Response is 25% of your Writing Task 1 score. Let that sink in. If you understand the prompt correctly but write the wrong tone, you're already docked points before your grammar even gets scored.
The band descriptors don't just ask "Did you answer the question?" They specifically ask "Did you use an appropriate register?" Register is just a fancy word for tone. Miss it, and Band 5 starts looking achievable. Band 7 stays locked behind the door.
Quick note: The IELTS band descriptors explicitly mention "appropriate register for an informal letter" and "appropriate register for a formal letter." Examiners are trained to spot tone mismatches. You need to be trained to avoid them.
IELTS General Training letters fall into three buckets. Know which one you're in the moment you open that prompt.
You're writing to someone you don't know well or don't know at all. A manager, a council official, a university admissions officer, a landlord. The relationship is professional, not friendly.
You're writing to a friend, family member, or someone you have a casual relationship with. The tone is relaxed, conversational, sometimes playful.
This one trips students up because it's genuinely in the middle. You're writing to someone you've met but don't know deeply, or a professional contact who's still friendly. Your boss's boss. A neighbour. A local business owner you recognize.
Semi-formal uses formal structure but slightly warmer language. You're not distant, but you're not mates either.
The prompt won't always say "write a FORMAL letter." You have to read between the lines. Here's what formal prompts actually say.
Example: "You have recently stayed at a hotel and found that several facilities were not working properly. Write a letter to the hotel manager describing what happened and asking for compensation."
The red flags for formal are: "write to the manager," "write to the council," "write to the principal," "complain about," "request," "inquire about." Any prompt involving authority, institutions, or problem-solving with strangers is formal.
Formal structure is always: Dear [Name/Title], opening (state purpose), body (explain), closing (request action), Yours sincerely/faithfully.
Too casual: "Hi there! I stayed at your hotel last week and honestly, nothing worked. The shower was broken, the TV was useless, and the bed was super uncomfortable. Could you maybe give me some money back? Cheers, Sarah"
Right tone: "Dear Manager, I am writing to formally lodge a complaint regarding my stay at your hotel from 15-18 August. During my visit, I encountered several maintenance issues, including a non-functional shower, faulty television, and a defective bed frame. These problems significantly impacted my comfort. I would appreciate compensation for the inconvenience caused. I look forward to your response. Yours sincerely, Sarah"
See the difference? One sounds like you texted a mate. The other sounds like you actually respect the hierarchy.
Informal prompts are equally obvious once you know what to look for. The language feels personal, friendly, sometimes emotional.
Example: "A friend of yours is going to your country to study next year. Write a letter describing your area, suggesting accommodation, and offering to help with settling in."
The red flags for informal are: "your friend," "a friend," "a relative," "write to someone you know," "tell them about," "catch up," "let them know." Any prompt about personal relationships or sharing experiences is informal.
Informal structure is: Dear [Friend's name], opening (personal greeting), body (share updates, news, advice), closing (warm sign-off), Best wishes/Cheers/Love.
Too formal: "Dear Jennifer, I trust this correspondence finds you in good health. I am writing to impart information regarding your prospective relocation to my country for tertiary education. It is my pleasure to recommend accommodation within close proximity to the educational institution. I remain available to assist with logistical arrangements. Yours faithfully, Tom"
Right tone: "Hi Jen! I'm so excited you're moving here! I've found a few places nearby that are really affordable and just 10 minutes from campus. The neighbourhood's brilliant, loads of students around. Let me know which one you like best and I'll help you sort out the paperwork. We're going to have such a laugh! Can't wait to see you. Cheers, Tom"
The formal version reads like a robot. The informal version reads like an actual friend.
Semi-formal is where the confusion lives. You're not writing to a stranger. You're not writing to a close friend either. You're stuck in the middle, and that middle ground trips people up.
Example: "Your neighbour is concerned about noise from your flat. Write a letter explaining the situation, apologizing, and suggesting a solution."
This is tricky because you might use formal letter structure (Dear [Name], formal greeting). But your language can be warmer. You're not grovelling to your neighbour. You're also not texting them.
Too casual: "Hey mate, sorry about the noise! My mates came over and we were just having a laugh. Won't happen again, promise! Let me know if it's a problem. Cheers"
Right tone: "Dear Mrs. Chen, I am writing to apologize for the noise from my flat last Friday evening. I had friends over and we were unaware that the sound was disturbing your peace. I take full responsibility and have asked my guests to keep the volume lower in future. I appreciate your understanding. If there are any further issues, please don't hesitate to contact me. Kind regards, Michael"
Semi-formal sits between. Formal structure, but you're not cold. Professional language, but warmer.
Your word choices are the biggest tone giveaway. Formal letters use completely different vocabulary than informal ones.
Formal words to master:
Informal words to master:
Honest tip: Read your letter out loud after you write it. If it sounds like someone's never spoken to another human, it's too formal. If it sounds like a WhatsApp message, it's too informal. The right tone feels natural but still clear.
Formal letters avoid contractions completely. Informal letters embrace them.
Formal: "I am writing" / "I will" / "I cannot" / "I have not"
Informal: "I'm writing" / "I'll" / "I can't" / "I haven't"
This is a quick way to signal tone across your entire letter. Use contractions consistently in informal letters. Cut them completely in formal letters. Semi-formal? Keep them to maybe two or three in a 150-word letter.
Before you submit: If you're writing formal, do a quick search for apostrophes. Formal letters shouldn't have any contractions. One stray "don't" can lower your register score.
You've written your letter. Now verify the tone matches the prompt. Use this five-step check (takes 90 seconds, saves you points).
This takes 90 seconds. It saves you band points. For a complete evaluation of your letter's formality level and band score potential, use our free IELTS letter tone checker.
Write your IELTS letter and use our IELTS writing checker to get instant feedback on your tone, register, and band score estimate. See exactly how examiners will evaluate your task response and register appropriacy.
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