After marking thousands of IELTS essays, I've noticed the same pattern: most students lose points in Coherence and Cohesion without realizing it. They think their ideas connect. They think their essay flows smoothly. Then the results come back: band 6.5 instead of 7.5. They have no idea why.
Here's the truth: examiners aren't hunting for fancy vocabulary or complex grammar when they assess this criterion. They're looking for something simpler and harder at the same time—can they follow your thinking without getting lost?
That's it. That's the whole game.
Let me show you exactly what that means, and more importantly, how to fix it in your own IELTS writing today.
I get asked this question constantly, and I'm glad, because understanding the difference changes how you write completely. Coherence is about logic: does paragraph two follow naturally from paragraph one? Can a reader track your argument without backtracking? Cohesion is about the glue: pronouns, linking words, repetition, transition phrases that show readers how ideas relate. Band 7 writers master both simultaneously.
Here's what kills most essays: you can have perfect cohesion with terrible coherence (transition words everywhere but ideas don't build on each other). Or a logical argument with almost no cohesive devices (exhausting to read). Coherence is about logic. Does each idea lead to the next? Coherence is invisible when working well—you just follow along.
Cohesion is about visible connectors. Without cohesive devices, even logical ideas feel choppy and fragmented.
Band 7+ example: "Urban planners have proposed three main solutions to traffic congestion. The first involves expanding public transportation networks, which reduces the number of private vehicles on roads. The second focuses on congestion pricing, a system that charges drivers during peak hours. Finally, cities can redesign streets to prioritize cycling and walking infrastructure."
Band 5-6 example: "Traffic is a problem. Cities need solutions. Public transportation is good. Congestion pricing charges money. Streets can change. Cycling is better. These things help."
The first has clear connectors (which, a system, finally). The second has ideas floating in space. One flows naturally; the other stutters.
The IELTS band descriptors are your roadmap. For band 7, the descriptor states: "Uses a range of cohesive devices appropriately although there may be some under or over-use, and some errors in their use. Paragraphs are generally well-organised and clearly linked."
Notice the key word: range. Band 6 writers typically use only linking words. Band 7 writers use linking words, pronouns, repetition, synonyms—they have a toolkit and know when to use each one. They deploy cohesive devices because the meaning demands it, not because they're ticking a box.
Band 8 says: "Uses a wide range of cohesive devices smoothly and flexibly to aid flow. Paragraphs are well-organised and clearly linked." That word "smoothly" is everything. Your cohesive devices disappear into the writing. Readers don't notice them; they just notice ideas connecting naturally.
I see the same errors repeatedly. Students understand what cohesive devices are, but they use them wrong. Here are the five biggest problems.
You write "However" or "Furthermore" because you've been told to use transition words. But the sentence after doesn't actually contradict or build on what came before.
Weak: "Climate change affects polar regions. Furthermore, young people spend too much time on social media."
Good: "Climate change affects polar regions most severely. As a result, wildlife habitats are disappearing at unprecedented rates."
The second actually justifies the transition word. There's real logic underneath.
You use "this," "it," "these," "that"—but readers have to guess what you're referring to. Good reference words clarify, not confuse.
Weak: "Many countries have implemented strict immigration policies. This has caused significant debate." (What does "this" mean? The policies? The implementation?)
Good: "Many countries have implemented strict immigration policies, a move that has sparked significant debate."
Now the reference is crystal clear.
You write a paragraph about education policy, then start the next with "It is important..." But which "it"? Your reader shouldn't play detective.
Weak: "Universities have faced funding cuts. It is therefore necessary to find alternative solutions. They must adapt quickly."
Good: "Universities have faced significant funding cuts. Educational institutions must therefore find alternative revenue sources. Universities can explore partnerships with private organizations or increase international student recruitment."
When you name the subject again, readers never get lost. This is stronger because it's clearer.
You learned to use synonyms to avoid repetition. But sometimes a synonym changes meaning slightly, and your argument gets fuzzy.
Weak: "Remote work has increased employee satisfaction. This flexible arrangement improves productivity. Telecommuting has drawbacks, however, including isolation." (Are these the same thing?)
Good: "Remote work has increased employee satisfaction. This arrangement also improves productivity. However, remote work does have drawbacks, including employee isolation."
You're using consistent terminology and building on it. The reader stays confident.
Essays where almost every sentence begins with "In addition," "Moreover," "Furthermore," or "However" sound mechanical. Robotic. Like an algorithm wrote it.
Overdone: "Smartphones have advantages. Furthermore, they are portable. Moreover, they provide instant communication. In addition, they offer entertainment. However, they can cause distraction. Nevertheless, they remain essential."
Good: "Smartphones have clear advantages: they're portable, provide instant communication, and offer entertainment. That said, they can cause significant distraction. Despite these drawbacks, smartphones remain essential for modern life."
The second uses colons, commas, and strategically placed transitions. It sounds like a person wrote it. That's band 7.
You can nail every cohesive device and still have a disconnected essay when paragraphs aren't organized logically. Most students write four good paragraphs that don't build on each other—just four isolated ideas sitting next to each other.
For IELTS Task 2 essays, use this structure:
Each paragraph should logically follow the one before it. Not just with a transition word, but with real reasoning. Paragraph 2 should feel like the natural next step after paragraph 1.
Quick test: Before writing each body paragraph, ask: "Why am I writing this here, now?" If you can't answer that, reorganize until each paragraph has a clear reason to come after the one before it. You can also use our free essay grading tool to see exactly where your organization breaks down.
A topic sentence tells readers what the paragraph covers and how it serves your overall position. Weak topic sentences are vague; strong ones are specific.
Weak: "Technology has many effects. Education is another important aspect. We must also consider the environment."
Good: "While technology creates new problems, its benefits to healthcare outweigh its drawbacks. The education sector shows a different pattern, where technology causes more problems than solutions. Environmental impact, however, depends entirely on how governments regulate the technology industry."
The second set does real work. Each tells you exactly what that paragraph argues and how it fits into your overall position. Your reader always knows where they're headed.
Let me show you how this works in practice. This is from a recent student (slightly edited).
The question: "Some people believe that governments should invest heavily in space exploration, while others think this money should be spent on solving problems on Earth. Discuss both views and give your opinion."
Original (Band 5-6 level):
"Space exploration is interesting. Some people think it is important. They believe we should go to space. Other people disagree. They say we should help people on Earth. Both views have points. In my opinion, I think we should do both. First, space exploration helps technology. Second, Earth problems are serious. Therefore, we need to solve them. But space also has benefits. We should try to do both things at the same time."
What's wrong? No real connections between ideas. Sentences don't build on each other. Pronouns are vague. Readers get confused about what "they" means and what "we" should do.
Improved (Band 7+ level):
"Space exploration remains one of the most contentious budget debates in government spending. Some argue that governments should prioritize space programs as engines of innovation and scientific discovery. Others maintain that these enormous investments would be better spent addressing urgent problems on Earth. Both viewpoints have merit, yet I believe that space exploration and terrestrial problem-solving are not mutually exclusive; governments can pursue both simultaneously through strategic funding.
Proponents of space exploration point to significant technological advances that have emerged from space programs. Satellite technology, water purification systems, and medical imaging devices all originated from space research. Moreover, space exploration inspires young people to pursue careers in science and engineering. These indirect benefits create long-term value for society. Additionally, understanding space helps us address Earth's challenges by providing data that terrestrial scientists would struggle to obtain otherwise.
Critics of space spending raise equally important concerns. Millions of people live in poverty, lack access to clean water, and suffer from preventable diseases. Redirecting space budgets to healthcare, education, and infrastructure would provide immediate relief to vulnerable populations. From this perspective, spending billions on space exploration seems irresponsible when basic human needs remain unmet.
However, this debate presents a false choice. Wealthy nations allocate their space budgets to a tiny percentage of overall government spending. NASA, for instance, receives less than 0.5% of the U.S. federal budget. Governments can fund both space research and social programs without compromising either.
In conclusion, the space exploration debate reflects a tension between long-term innovation and immediate need. However, rather than choosing between them, governments should recognize that space programs drive technological advancement that ultimately benefits all citizens, including those facing urgent challenges today."
The differences here show real coherence and cohesion: clear topic sentences that introduce each idea's purpose, pronouns with specific antecedents, transition words that actually connect logical steps, and a progression where each paragraph builds naturally on the one before. The student uses IELTS essay topics to practice this exact structure repeatedly before the test.
Here's what examiners look for when assessing cohesion. These aren't just fancy words to sprinkle in; they're tools you use strategically.
These show relationships between ideas: "because," "as a result," "in contrast," "for example," "nevertheless." Use them when you have a genuine logical connection.