By vs. With – Which is Correct?

Both by and with are correct, but they express different relationships. Use by to identify the agent, method, deadline, or proximity; use with to identify an instrument, accompaniment, possession, or manner. Choosing the right preposition depends on whether you emphasize who or what caused an action, or what was used.

By or With – Which is Correct?

By and with are both correct English prepositions, but they are not usually interchangeable. Use by when you want to identify the person or force responsible for an action, the method used, a deadline, or something nearby. Use with when you want to identify a tool, an accompanying person, a characteristic, or the manner in which something happens.

The same attention to nuanced relationships helps when choosing between Compare To vs. Compare With in formal writing.

Compare these sentences:

• The portrait was painted by Elena. The sentence identifies the artist or agent.
• Elena painted the portrait with a fine brush. The sentence identifies the instrument.

The Best Trick to Remember the Difference

Use the “who versus what” test. If you are asking who performed the action?, choose by. If you are asking what tool, person, or quality was involved?, choose with. For example, “The cake was decorated by Sam with chocolate roses.” Sam is the person responsible, while chocolate roses are the decorative material.

Word	Part of Speech	Meaning	Example
by	Preposition	Identifies an agent, method, deadline, or location	The novel was written by Mira.
with	Preposition	Identifies a tool, companion, feature, or manner	She opened the box with a key.

How to Use By

Use by in several important ways. In passive sentences, it introduces the person, group, or force that performs the action: The bridge was designed by an award-winning engineer. It can also describe a method of travel or communication, such as by train, by email, or by hand.

By also expresses a deadline, meaning “at or before a particular time.” In addition, it can indicate location or movement near something, as in We sat by the window or She walked by the library. In formal and casual English alike, the intended meaning comes from the surrounding phrase.

Example 1: The documentary was directed by an independent filmmaker.

Example 2: Please submit your application by Friday.

Example 3: We traveled by bus and communicated by text message.

Etymology of the Word By

By comes from Old English bī, meaning “near,” “beside,” or “by means of.” Its meanings expanded over time. The ideas of proximity, agency, and method remain connected: something can happen near an agent, through an agent, or by means of a particular process.

How to Use With

Use with to show association, accompaniment, possession, or the instrument used to perform an action. It can mean that someone or something is present alongside another person or thing, as in Jordan arrived with her sister. It can also identify a tool or material, as in He repaired the chair with glue.

With can describe a feature or quality, such as a house with a red door, and it can express manner or attitude, as in She answered with confidence. It may also appear in phrases that describe conflict or agreement, including argue with, agree with, and work with.

Example 1: The child cut the paper with scissors.

Example 2: I went to the conference with my colleague.

Example 3: The manager handled the difficult conversation with patience.

Etymology of the Word With

With comes from Old English wiþ. It originally carried meanings connected with opposition, proximity, and association. Over time, its modern meanings developed to include accompaniment, tools, possession, and manner.

Related Concepts

Understanding the broader roles of prepositions makes the difference between by and with easier to recognize.

• Prepositions: Prepositions connect nouns or pronouns to other parts of a sentence and express relationships involving time, place, method, agency, or association.
• Agent in a passive sentence: In a passive construction, by commonly introduces the person or thing responsible for an action, as in The song was performed by the choir.
• Instrument or means: With often introduces the object used to complete an action, as in She unlocked the door with a card.
• Method versus tool: By usually describes a general method, such as by train or by email, while with usually names a specific instrument, such as with a pen.

Examples from Media and Literature

Well-known works frequently use by and with to show authorship, agency, method, tools, or accompaniment. The following examples illustrate these patterns without relying on a single fixed phrase.

• Literature: A novel is commonly described as a work “by” its author because by identifies the creator, such as a novel by Jane Austen.
• Film: A movie may be presented as directed “by” a particular filmmaker, identifying the person responsible for directing it.
• News: Reports often state that a statement was issued “by” a government department, identifying the issuing authority.
• Music: A song may be performed “by” a singer and recorded “with” a particular instrument or ensemble.
• Everyday media: Instructions may tell readers to submit a form “by” email and complete it “with” a black pen.

Practice Exercises

Choose the correct word to complete each sentence.

1. The package was delivered ___ a courier.
2. She opened the envelope ___ a letter opener.
3. Please arrive ___ 8:00 a.m.
4. He went to the museum ___ his classmates.
5. The team traveled ___ train and carried its equipment ___ them.

Answer Key

1. by — “By a courier” identifies the person who delivered the package.
2. with — “With a letter opener” identifies the tool used.
3. by — “By 8:00 a.m.” expresses a deadline.
4. with — “With his classmates” expresses accompaniment.
5. by, with — “By train” describes the method of travel, while “with them” expresses possession or accompaniment.

By Synonyms

Synonym	Definition
Through	By means of a process, route, or method
Via	By way of a route or medium; often more formal
Before	At or before a specified deadline
Beside	Next to or near something

With Synonyms

Synonym	Definition
Alongside	Together with or next to someone or something
Together with	In the company of or in combination with
Using	By means of a particular tool or object
Including	Containing or involving a particular person or thing

Frequently Asked Questions

Question 1: Should I use “by” or “with” to describe a tool?
Use with for a specific physical tool or instrument: She wrote with a pencil. Use by for a general method: She sent the message by email.

Question 2: Is it “written by” or “written with” an author?
Use written by to identify the author: The book was written by Carlos. Use written with only when referring to the instrument or material used for writing, such as written with a fountain pen.

Question 3: Is it “travel by” or “travel with”?
Use travel by for the mode of transportation, such as travel by car or travel by plane. Use travel with for a companion or possession, such as travel with my family or travel with one suitcase.

Question 4: Does “by” always identify a person?
No. By can identify an agent, but it can also express a method, deadline, location, measurement, or gradual change. Examples include by hand, by noon, by the door, and one by one.

Conclusion

By and with are both correct, but they serve different purposes. Choose by for an agent, general method, deadline, or nearby location. Choose with for a tool, companion, feature, material, or manner. Pro Tip: Precise preposition choices make your writing clearer and help protect your professional reputation.