Increased By vs Increased To in IELTS Writing Task 1

In IELTS Writing Task 1, a tiny preposition can change the whole meaning of a number. Many learners write "increased by" and "increased to" as if they are the same. They are not. If you use the wrong one, the sentence may describe a completely different figure.

The basic rule is simple: use "increased by" for the amount of change, and use "increased to" for the final number. This is one of the easiest IELTS graph description mistakes to fix because the grammar is clear once you connect it to the numbers.

The difference between by and to

Use "by" when you are talking about how much something changed. For example, "The percentage increased by 20 percentage points" means the change was 20. It does not tell us the final number unless the previous number is also given.

Use "to" when you are talking about the final result. For example, "The percentage increased to 60%" means the final figure was 60%. It does not tell us exactly how much it increased unless we know the starting point.

Now combine them: "The percentage increased by 20 percentage points to 60%." This tells us both the change and the final number. If the starting figure was 40%, the movement was from 40% to 60%.

Use from and to for the full movement

When you want to show the whole movement, "from...to" is usually the clearest choice: "The number of users rose from 2 million to 5 million." After that, you can add the amount of change if it is useful: "This was an increase of 3 million."

Be careful with percentages. If something rises from 40% to 60%, the change is 20 percentage points, not simply "20 percent" in many Task 1 contexts. You do not need to over-explain this in every report, but you should avoid sentences that make the data inaccurate.

Also remember that "doubled" and "halved" already describe the size of change. Write "The figure doubled from 30 to 60," not "increased by doubled." Write "The amount halved from 80 to 40," not "decreased by halved." These words are useful, but only when the data truly supports them.

A quick correction check before you finish

Before you submit a Task 1 report, check every sentence with numbers. Ask yourself: Am I describing the starting number, the amount of change, or the final number? If it is the amount of change, you probably need "by." If it is the final figure, you probably need "to." If you want the full movement, use "from...to."

Try this example: "The number increased ___ 20% ___ 60%." The correct answer is "by 20 percentage points to 60%" if the starting point was 40%. For simpler practice, you can remember it as: change by, final number to.

Small errors in Task 1 often repeat across the whole report. If you keep losing accuracy in graph language, you can get detailed correction through Paid Essay Feedback. A teacher can point out whether your number language, comparisons, overview, and grammar are working together clearly.

The best Task 1 writing is not full of difficult words. It is accurate, controlled, and easy to understand. Mastering increased by vs increased to is a small step that makes your data description much more reliable.