Increase and Its Opposite: Simple Guide
The opposite of increase is decrease. When something goes up in number, size, or strength, it increases. When it goes down, it decreases. This guide explains how to use both words correctly in everyday English, with clear examples and common mistakes to avoid.
Quick Answer: Increase vs. Decrease
Increase means to become larger or greater. Decrease means to become smaller or less. Both words can be verbs (actions) or nouns (things).
- Increase (verb): Sales increased by 20% last month.
- Decrease (verb): The temperature decreased overnight.
- Increase (noun): We saw an increase in website traffic.
- Decrease (noun): There was a decrease in customer complaints.
How to Use Increase and Decrease in Real Life
These words appear in many situations: work emails, news reports, casual conversation, and academic writing. The tone changes depending on where you use them.
Formal Tone (Emails, Reports, Presentations)
In professional settings, increase and decrease are direct and clear. They work well in business writing.
- We need to increase our production capacity by 15%.
- The budget decrease will affect next quarter’s projects.
- Please note the increase in shipping costs.
Informal Tone (Conversation, Text Messages)
In casual talk, people often use simpler words like go up and go down instead of increase and decrease. But the formal words are still understood.
- Prices went up again. (instead of increased)
- My energy levels go down after lunch. (instead of decrease)
Email Context
In emails, increase and decrease sound professional. Use them when you need to be precise.
- We have decided to increase the team size.
- Could you explain the decrease in response rates?
Conversation Context
In everyday speech, people often say get bigger or get smaller. But using increase and decrease shows a wider vocabulary.
- My workload increased this week.
- His interest in the project decreased over time.
Comparison Table: Increase vs. Decrease
| Feature | Increase | Decrease |
|---|---|---|
| Meaning | Become larger or greater | Become smaller or less |
| Verb form | increase (increased) | decrease (decreased) |
| Noun form | increase | decrease |
| Common synonyms | rise, grow, go up | fall, drop, go down |
| Opposite pairs | increase / decrease | decrease / increase |
| Formal use | Very common | Very common |
| Informal use | Less common (use “go up”) | Less common (use “go down”) |
Natural Examples
Here are real-world sentences showing how native speakers use these words.
- The company increased its prices due to higher costs.
- We need to decrease our expenses this month.
- There has been a steady increase in online shopping.
- A decrease in rainfall caused the drought.
- She increased her daily exercise from 20 to 40 minutes.
- The doctor advised him to decrease his salt intake.
- Population increased rapidly in the 20th century.
- After the holiday, sales decreased sharply.
Common Mistakes
Even advanced learners sometimes make errors with these words. Here are the most frequent ones.
Mistake 1: Using the wrong preposition
Incorrect: The price increased with 10%.
Correct: The price increased by 10%.
Explanation: Use by to show the amount of change, not with.
Mistake 2: Confusing increase as a verb and noun
Incorrect: There was an increase of sales.
Correct: There was an increase in sales.
Explanation: As a noun, increase is followed by in, not of.
Mistake 3: Using decrease when you mean reduce
Incorrect: We need to decrease the price.
Correct: We need to reduce the price.
Explanation: Decrease often describes something that happens naturally. Reduce is more common when someone takes action. Both are correct, but reduce sounds more active.
Mistake 4: Forgetting the opposite pair
Incorrect: If you increase the temperature, it will increase.
Correct: If you increase the temperature, it will decrease the cooling effect.
Explanation: Always check that you are using the correct opposite word for the context.
Better Alternatives and When to Use Them
Sometimes increase and decrease are not the best choice. Here are alternatives for different situations.
When to use “rise” and “fall”
Use rise and fall for gradual changes, especially in graphs or trends.
- Stock prices rose steadily. (better than “increased” in financial news)
- Temperatures fell overnight. (more natural than “decreased”)
When to use “grow” and “shrink”
Use grow and shrink for size, business, or living things.
- The company grew by 30% last year.
- The forest area shrank due to farming.
When to use “boost” and “cut”
Use boost and cut for deliberate actions.
- We need to boost sales this quarter. (stronger than “increase”)
- The government cut funding for the program. (more direct than “decrease”)
When to use “raise” and “lower”
Use raise and lower for levels, prices, or volume.
- Please raise your hand.
- Can you lower the volume?
Mini Practice: Test Yourself
Choose the correct word: increase or decrease.
Question 1: The number of students in the class _____ from 30 to 45.
Answer: increased
Question 2: We need to _____ our electricity usage to save money.
Answer: decrease
Question 3: There was a sudden _____ in temperature last night.
Answer: decrease
Question 4: The company reported a 10% _____ in profits this year.
Answer: increase
Frequently Asked Questions
1. Can increase and decrease be used as both verbs and nouns?
Yes. As verbs: Sales increased. As nouns: There was an increase in sales. The spelling stays the same, but the pronunciation changes slightly. The verb has stress on the last syllable (in-CREASE), and the noun has stress on the first syllable (IN-crease).
2. What is the difference between “increase by” and “increase to”?
Increase by tells you the amount of change. Prices increased by $5.
Increase to tells you the final amount. Prices increased to $25.
The same rule applies to decrease.
3. Is it correct to say “decrease down”?
No. Decrease already means to go down, so adding down is redundant. Say decrease or go down, but not both together.
4. What are some common opposite pairs with increase and decrease?
Here are a few common pairs you will see in Beginner Vocabulary Pairs:
- increase / decrease
- rise / fall
- grow / shrink
- gain / lose
- add / subtract
Final Tips for Using Increase and Decrease
Remember these three points:
- Use “by” for the amount of change. Increased by 5%.
- Use “in” after the noun form. An increase in demand.
- Choose simpler words in casual conversation. Go up / go down are fine with friends.
For more opposite word pairs, visit our Common Opposites section. If you have questions about this guide, check our FAQ page or contact us. We also have a full Antonyms with Examples collection for deeper learning.
Understanding increase and decrease will help you describe changes clearly in English. Practice using them in your own sentences, and soon they will feel natural.
