IELTS Writing Task 1 Tenses: Which Tense for Which Chart

Choosing the wrong tense is one of the easiest ways to lose marks in Writing Task 1, and one of the easiest to fix. When I started reading learners' Task 1 answers, I noticed that most tense errors came from one habit: writing the whole report in the past tense, whatever the chart showed. The better habit is to let the chart tell you which tense to use.

This guide gives you one rule, four patterns and a short checklist. It applies to the Academic Task 1 (charts, graphs, maps and processes), where you write at least 150 words. For the General Training letter, tense follows the situation you are writing about, not the data.

The one rule: follow the time on the chart

Look at the time labels first. Tense follows time, not the chart type.

• Every date is in the past (for example 1995 to 2010): use the past simple.
• Dates run into the future (for example 2020 to 2040): use the past simple for past years and future forms for later years.
• No dates at all (a process, a cycle, a static table of "this year" figures): use the present simple.
• The chart gives a single present moment (for example "in 2024" when the test is set in 2024): use the present simple.

Everything else in this article is a variation on that rule.

Pattern 1: line graphs and bar charts with past dates

When the whole period has finished, describe it in the past simple, and use the past perfect only if you need to show one event happened before another.

Between 2000 and 2015, the number of cyclists rose steadily, while car use fell slightly.

By 2010, cycling had overtaken walking as the most popular choice.

The second example uses the past perfect because the sentence looks back from 2010 to something that happened earlier. You do not need the past perfect in every answer. One or two well-placed uses are plenty, and plain past simple is safe everywhere else.

Avoid the present perfect ("has risen") for a closed period. It signals a link to the present, so it clashes with dates that are clearly over.

Pattern 2: charts that include projections

Many line graphs end with a forecast. Split the report at the point where data stops being a record and becomes a prediction.

From 2005 to 2020, the proportion of older residents grew from 12% to 19%.

It is predicted to reach 25% by 2040.

Useful forecast structures include "is expected to", "is projected to", "will probably" and "is forecast to". Pick the one that fits the label on the chart. If the chart is headed "projected", use "projected". Do not turn a prediction into a certainty with a bare "will" if the source shows an estimate.

A common mistake is to describe a forecast year in the past tense ("in 2040, the figure reached 25%"). If the year has not happened yet, it cannot have reached anything.

Pattern 3: tables and pie charts with one moment in time

A pie chart or table showing a single year, with no change over time, calls for the present simple if the year is the present or unstated, and the past simple if the year is clearly past.

Housing accounts for the largest share of household spending, at 32%.

Food and transport come next, with 18% and 15% respectively.

If the title says "in 2018", stay in the past simple. If there is no date, use the present simple. Do not mix them inside one paragraph.

Pattern 4: maps and processes

A process describes how something works, so it takes the present simple, usually in the passive voice because the doer is not the focus.

First, the raw material is collected and transported to the factory.

It is then crushed, heated and moulded into shape.

Maps are the exception that confuses people most. Use the tense that fits the dates:

• A map comparing "1990" with "2020": past simple for changes ("a new road was built", "the forest was cleared") and present simple for what exists in the later map if the question frames it as current.
• A map comparing the present with a future plan: present simple for what exists now, will or "is going to" for the plan ("a shopping centre will replace the car park").

For both maps and processes, use the passive when you describe changes ("the school was extended") and active when the thing itself is the subject ("the river runs north").

The three tense mistakes I see most

Mixing tenses without a reason. Switching between past and present inside one paragraph reads as a grammar error, even when each sentence is correct on its own. Change tense only when the time changes.

Using "will" for unlabelled data. Learners sometimes write "the figure will rise" about a trend that is already in the past. If the data shows it, report it in the past.

Opening with the wrong tense. The overview sentence sets the tone. If the chart covers 1980 to 2010, begin "The chart shows how..." (present simple, because you are describing the chart itself) and then move into the past for the data. The introduction describes the document in the present; the body describes the events in the tense the dates demand.

The graph illustrates how energy consumption changed in three countries between 1980 and 2010.

Notice "illustrates" is present and "changed" is past, and both are correct.

A 60-second tense check

Before you write your first body sentence, spend a minute on this:

1. Circle every date or time label on the chart.
2. Is the last date past, present or future?
3. If the last date is future, mark the exact year where data becomes forecast.
4. Choose your introduction verb in the present simple.
5. Write one sentence for each phase in the correct tense.

When you finish, reread only the verbs. Tick each one against the time it describes. This takes about a minute and catches almost every tense slip.

How to practise

Take any past Task 1 question and write only the overview and the first body paragraph, then check the verbs against the dates. Repeat with a process and a map. After a week of this, choosing a tense stops being a decision and becomes a reflex.

If you want feedback on your own Task 1 answers, you can practise with AI feedback in Toey's IELTS tool. The AI grade is an estimate, and it should not replace a teacher or an official test. See Toey IELTS.