Here's something I see constantly in my classes: students write the same letter tone for everything. A formal complaint sounds chatty. A friendly letter to a mate sounds stiff. This is where most students mess up, and it costs them band points.
The IELTS General Training Writing Task 1 is deceptively simple on the surface. You get a prompt, you write a letter, done. But here's what catches people off guard: the band score difference between someone who nails the tone and someone who doesn't? Often 1 to 2 bands. That's the difference between a 6 and a 7, or a 7 and an 8. One wrong choice of words can flatten your score.
Let me be blunt: understanding the three IELTS letter types isn't optional. It's the foundation of Task 1. In this post, I'll break down exactly what examiners want to see in each one, show you real examples, and give you a system for getting the tone right every single time.
Think about it from the examiner's perspective. They're marking your "Task Response" and "Coherence and Cohesion"—two of the four IELTS writing band descriptors. They're looking for evidence that you understand context. That you can adjust your language for different situations. That you're not a robot spitting out template sentences.
The IELTS band descriptors for writing specifically call this out. A Band 7 response shows "register is appropriate and consistent." A Band 6? "Register is mostly appropriate." The margin is tiny. One wrong "mate" in a formal letter costs you points. One "Yours faithfully" in a semi-formal letter to someone you know makes you sound robotic.
Here's the real kicker: tone affects everything downstream. Your vocabulary choices. Your sentence structure. Your opening and closing phrases. Get it wrong, and even correct grammar looks awkward. Get it right, and you sound like a professional communicating appropriately.
There are three tones you need to master for IELTS General Training:
Most students get informal right. They know how to text a friend. The problems start with formal and semi-formal. Those are where the nuance lives, and that's where we're going to focus.
A formal letter is professional communication. You're asking for something, complaining about something, or requesting information from a company or government body. The person reading it doesn't know you. They're not your friend. They're evaluating your request on its merits.
Here are the non-negotiables for an IELTS formal letter:
Let me show you the difference between weak and strong:
Weak (too informal, no professional distance):
"Hi there, I'm writing because I'm really upset about my booking. I booked a room for next week but the price changed and now it's way more expensive. This isn't fair and I want you to fix it. Let me know what you can do about it. Thanks!"
Strong (formal, professional, structured):
"Dear Sir or Madam, I am writing to bring to your attention a discrepancy regarding my recent booking confirmation. The price quoted at the time of reservation has increased significantly. I would appreciate if you could investigate this matter and restore the original rate. I look forward to your prompt response. Yours faithfully, [Name]"
Notice the difference? The strong version sounds like an adult dealing with a business problem. The weak version sounds like someone complaining to a friend. Examiners notice this immediately. Your band score reflects it.
Quick tip: Read your formal letters aloud. If you hear yourself speaking it naturally, it's probably too casual. Formal writing should sound slightly stiff when read aloud. That's actually correct.
Here's the thing: semi-formal is where most students panic. It's not quite formal, not quite casual. How do you balance politeness with friendliness?
You use semi-formal when writing to someone you have a relationship with, but it's still professional. Your landlord. A hotel manager. A teacher. A manager at your gym. Someone in the middle ground where you're not strangers, but you're not mates either.
The rules are looser than formal but tighter than informal:
Let me show you a semi-formal example. Imagine you're writing to your landlord about a repair issue:
Weak (too formal, sounds robotic and distant):
"Dear Mr. Johnson, I regret to inform you that the heating system in the property has ceased to function. I request that you arrange for immediate professional inspection and repair. I await your response. Yours faithfully, [Name]"
Strong (semi-formal, warm but professional):
"Dear Mr. Johnson, I'm writing to let you know that the heating system isn't working properly. I've tried the usual troubleshooting, but I think it needs a professional to have a look. Could you arrange for a repair when you get a chance? Let me know if you need any further details. Best regards, [Name]"
See the difference? The strong version sounds like someone who respects the landlord but isn't afraid to speak naturally. It's not overly formal ("I regret to inform you"), and it's not casual either ("Hey mate, the heating's broken, fix it"). This is the tone that trips up most students. You're not distant enough for formal, but not close enough for informal. Split the difference: be friendly, use contractions, but keep the structure and professionalism intact.
Informal letters are the easiest for tone, hardest for structure. Students often write these like text messages: rambling, no clear organisation, jumping between ideas. And yes, you'll lose marks for Coherence and Cohesion.
You're writing to a friend or family member. Someone you know well. Here's what you can do:
But here's what students forget: informal doesn't mean disorganised. Your letter still needs clear paragraphs. Each paragraph should focus on one idea. You still need to answer the prompt completely.
Weak (disorganised, rambling, no structure):
"Hi Sarah! How are you? I've been so busy lately, work is crazy and I haven't had time to think. Oh, I bought a new laptop the other day, it's amazing. Anyway, I wanted to tell you about my holiday plans. I'm thinking of going to Thailand. Have you been there? I'd love to visit the beach and try the local food. Also, I got a promotion at work! Isn't that great? I'm still getting used to it. What have you been doing? Write back soon! All the best, [Name]"
Strong (informal but organised):
"Hi Sarah! Hope you're doing well. I'm writing because I wanted to tell you about some exciting news. I got a promotion at work! It's been something I've been hoping for, and I'm still getting used to all the new responsibilities. Work has been pretty hectic, but in a good way. Anyway, I've been thinking about taking a holiday to Thailand next month. I know you've travelled there before, so I'd love to hear about your favourite spots. I'm especially keen on visiting the beaches and trying authentic local food. Let me know what you'd recommend! All the best, [Name]"
Both are friendly. But the strong version has clear paragraphs: opening, news about the promotion, questions about Thailand. The weak version jumps around. It talks about work, then laptop, then holiday, then promotion again. That's incoherent. You'd lose marks for Coherence and Cohesion.
Quick tip: Plan your informal letters just like formal ones. Even though they're conversational, they still need structure. Three paragraphs minimum: introduction, main content (organised into clear points), closing.
If you're unsure whether something's appropriate, check these lists. They'll anchor your tone choices:
Formal Letter Phrases:
Semi-Formal Phrases:
Informal Phrases:
I've seen students improve their band by 0.5 just by using these phrases correctly. They sound natural when you use language that matches the tone you're aiming for.
Don't overthink the structure. Use this framework for any letter, then adjust the language:
Paragraph 1 (Opening, 2–3 sentences): Say why you're writing. Be direct.
Paragraphs 2–3 (Main body, 4–6 sentences per paragraph): Explain the situation, give details, answer the prompt completely.
Paragraph 4 (Closing, 2–3 sentences): Restate what you need or want to happen. End with a polite closing phrase.
That's it. Four paragraphs, roughly 40–50 words each. You'll hit 150–200 words. You'll have coherent structure. You won't ramble.
Quick tip: Spend 2 minutes planning before you write. Write down your four main ideas. Match them to your four paragraphs. Then write. Students who skip this step write longer, messier letters and run out of time.
The prompt will always tell you who you're writing to. Here's how to identify the right tone: