How to write the Task 1 overview
Omit it and Task Achievement is capped, whatever else you do. It is two sentences, it takes two minutes, and it is the highest-value writing in the task.
What it is
One or two sentences stating what is most striking about the data as a whole. Not the first data point, not a summary of your paragraphs — the thing a reader would notice standing back from the chart.
It contains no specific figures. Figures are detail, and detail belongs in the body. An overview with numbers in it is usually a body sentence that has wandered.
In 1990 sales were 20%, rising to 35% in 2000 and 60% in 2010.
Overall, sales rose steadily across the period, with the sharpest growth in the final decade.
Where it goes
Second. Paraphrase the prompt in one sentence, then the overview, then the detail paragraphs.
Write it second too, not last. Left to the end it gets rushed or dropped when time runs short, and it is the last thing in this task you can afford to lose. Deciding what is striking before you write the detail also makes the detail easier to select.
What to look for, by chart type
| Chart | The striking thing is usually |
|---|---|
| Line graph over time | Overall direction, and where it changed |
| Bar chart comparing categories | Highest and lowest, and the size of the gap |
| Pie charts | The dominant slice, and what changed between them |
| Table | The row or column that behaves unlike the rest |
| Process diagram | How many stages, whether it is linear or a cycle, start and end |
| Map | The overall character of the change: more built up, reorganised, expanded |
Process diagrams and maps are the ones candidates freeze on, because "trend" does not apply. They still have an overview: a process has a number of stages and a shape, a map has a direction of change.
Two habits that make it easy
Signal it. Overall, In general, or It is clear that at the start makes the overview unmistakable to a marker reading quickly. This is one of the few places in IELTS where a formulaic opener helps rather than hurts, because the reader is looking for exactly this move.
Compare something. Most strong overviews contain a comparison — higher than, unlike, in contrast to — because comparison is what turns a description into an observation.
When one sentence is not enough
With two charts, or a chart with two clearly different groups, two sentences usually serve better: one per element. That is still an overview as long as neither sentence carries figures.
More than three sentences and you have started the body early. Stop.
The check
Cover your body paragraphs and read only the introduction and overview. Could someone who has never seen the chart describe roughly what it shows? If not, the overview is doing the reader's work rather than yours.
It is the first of the six failures in common mistakes in Academic Task 1, and it costs more than the other five together.
Is your overview doing its job? IELTS Writing Checker scores Task Achievement separately, so you can see whether a missing overview is capping your band. Try it — writing is free, or see pricing.