Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
return to sender
Grammar usage guide and real-world examplesUSAGE SUMMARY
"Return to sender" is a correct and usable phrase in written English, usually used to indicate that a letter or package has been sent back to the original sender.
For example: "The package was marked 'return to sender' and sent back to the sender's address."
✓ Grammatically correct
News & Media
Science
Wiki
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
58 human-written examples
"Return to sender," he said.
News & Media
"Return to sender," he calls it.
News & Media
"I guess we need to return to sender".
News & Media
"She wrote upon it: Return to sender, address unknown".
News & Media
How callously I'd marked the gift "return to sender".
News & Media
The firm's mail room returned the envelopes unopened and marked "return to sender".
News & Media
But such innovations will happen only if national governments can be discouraged from stamping the commission's proposals "return to sender".
News & Media
A measure to shore up the ailing postal system might as well have been marked return to sender.
News & Media
In the copy, a phallic cactus appears on the plinth together with the words "return to sender".
News & Media
Well, the album did send a message, and that message has been received and marked: Return to Sender.
News & Media
But restoration notices marked "return to sender" have been piling up in the parole commission's office at a rapid clip.
News & Media
Expert writing Tips
Best practice
Use "return to sender" when you want to clearly indicate that an item or message could not be delivered to the intended recipient and is being sent back.
Common error
Avoid using "return to sender" in contexts where a simple rejection or refusal is meant, as it specifically implies a failed delivery attempt.
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "return to sender" functions primarily as an imperative, often used to instruct the postal service or another party to send something back to its origin. As confirmed by Ludwig, it is correct and usable in written English.
Frequent in
News & Media
56%
Wiki
16%
Science
12%
Less common in
Formal & Business
8%
Reference
4%
Encyclopedias
0%
Ludwig's WRAP-UP
The phrase "return to sender" is a common and grammatically sound way to indicate that an item should be sent back to its originator because it couldn't be delivered. Ludwig confirms its usability in written English. Predominantly found in News & Media, Wiki and Science contexts, the phrase is generally neutral in tone but can become informal. When using the phrase, ensure it aligns with a failed delivery attempt rather than a simple refusal. Alternatives include phrases like "send back", "undeliverable as addressed", and "refused delivery".
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
send back
Focuses on the action of sending something back without specifying the reason.
undeliverable as addressed
A formal way of indicating that an item could not be delivered to the specified address.
refused delivery
Highlights the explicit refusal of a delivery by the recipient.
mail undeliverable
Specifically refers to mail that cannot be delivered.
reject and redirect
Emphasizes the refusal and subsequent forwarding of an item or message.
revert to source
Emphasizes the action of returning to the original source or sender.
forward to originator
Specifies the action of forwarding something back to its original source.
bounce back
Suggests a rebounding effect, often used in the context of emails or messages.
address unknown
Indicates that the recipient's address is not known or valid.
not accepted
A general term for refusing something that has been sent.
FAQs
What does "return to sender" mean?
The phrase "return to sender" indicates that an item, typically mail or a package, could not be delivered to the intended recipient and is being sent back to the original sender.
When should I write "return to sender" on an envelope?
Write "return to sender" on an envelope if the recipient is unknown, has moved, or the mail is otherwise undeliverable at the specified address. You can also use alternatives like "address unknown".
What are some alternative phrases for "return to sender"?
Alternatives include "send back", "undeliverable as addressed", or "refused delivery", depending on the specific reason for the return.
Is it rude to write "return to sender" on mail addressed to a previous resident?
No, it is not rude. Writing "return to sender" on mail for a previous resident helps ensure they no longer receive mail at your address and prevents clutter. This is preferable to discarding the mail.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
84%
Authority and reliability
4.5/5
Expert rating
Real-world application tested