Lock sth in Meaning, Examples & How to Use in English

What Does “Lock sth in” Mean?

“Lock sth in” means to secure or fix something firmly, usually an agreement, price, or plan, so it cannot be changed later.

Introduction

The phrase lock sth in is a common phrasal verb in English used to describe the act of making a decision, price, or arrangement definite and unchangeable. When you lock something in, you are committing to it firmly. This expression is often used in business, travel bookings, and everyday conversations to show that a deal or plan is confirmed and secured. Understanding the lock sth in meaning helps you communicate clearly about agreements and decisions, making your English sound more natural and professional.

Quick Info Box

• Phrasal verb: lock something in
• Type: Transitive
• Level: B2
• Short meaning: To fix or secure something so it cannot change

Structure (Grammar Rules)

“Lock sth in” is a separable phrasal verb, meaning the object can come between the verb and the particle or after the particle.

• lock something in (correct) – e.g., lock the price in
• lock in something (also correct) – e.g., lock in the price

Both forms are acceptable, but placing the object between “lock” and “in” is more common.

How to Use “Lock sth in”?

You use “lock sth in” when you want to express that a decision, price, or arrangement is finalized and cannot be changed. It is often used when talking about contracts, prices, schedules, or plans.

• Lock in a price to avoid future increases.
• Lock in a date for an appointment or event.
• Lock in a deal or contract to make it official.

Examples

When booking flights, it’s important to lock in a good price early.

• We locked the contract in last week, so the terms won’t change.
• The company locked in a low interest rate for the loan.
• She locked in the date for her wedding months in advance.
• If you want to save money, lock in your hotel reservation now.

Here are more examples of lock sth in in a sentence:

• They locked in the price before the market went up.
• Make sure to lock in your subscription to get the discount.

Common Mistakes

Sometimes learners confuse the word order or use the wrong preposition.

• Incorrect: Lock in the price it.
• Correct: Lock the price in.
• Incorrect: Lock on the date.
• Correct: Lock in the date.

Remember, the particle “in” always follows “lock” directly or after the object.

Differences / Synonyms

“Lock sth in” is similar to “secure,” “confirm,” or “fix,” but it often implies making something officially unchangeable.

• Secure: Means to obtain or protect something but not always permanent.
• Confirm: Means to agree or verify but may not imply permanence.
• Fix: Can mean to set something firmly but less formal than “lock in.”

For example, you can “secure a booking” but “lock in the price” means the price will not change.

Common Collocations

Here are common objects used with “lock sth in” and what they mean:

• Price: To guarantee a cost won’t increase.
• Date: To set a specific day for an event.
• Contract/deal: To make an agreement official and unchangeable.
• Interest rate: To fix the cost of borrowing money.
• Reservation: To confirm a booking firmly.

Related Phrasal Verbs

Here are related phrasal verbs of lock sth in:

• Lock Sth Away
• Lock Yourself Out Of Sth
• Lock Sb In
• Lock Sth Out
• Lock Sb Up

Real-life Dialogue

Here is a conversation where two friends discuss locking in plans:

Anna: Have you locked in the date for the conference yet?

Ben: Yes, I locked it in for next Friday. I don’t want it to change again.

Anna: Good idea! I’ll lock in my hotel reservation today.

Practice

Complete the sentences by choosing the correct form:

• I want to ______ the price ______ before it goes up.
  • a) lock in
  • b) lock it in
  • c) lock the price in
• They ______ the contract ______ last week.
  • a) locked in
  • b) locked it in
  • c) locked the contract in
• Make sure to ______ your reservation ______ early.
  • a) lock in
  • b) lock it in
  • c) lock the reservation in

FAQs

• What does “lock sth in” mean?

  It means to secure or fix something so it cannot be changed later.
• Is “lock sth in” separable?

  Yes, you can place the object between “lock” and “in” or after “in.”

• Can I use “lock sth in” for prices?

  Yes, it is commonly used to fix prices or rates.
• What is a common mistake with “lock sth in”?

  Putting the object in the wrong place, like “lock in the price it.”

• What are synonyms for “lock sth in”?

  Secure, confirm, fix (but “lock in” implies more permanence).