Care of, abbreviated c/o, is an addressing device for routing correspondence through another person or place. It should be kept distinct from attention lines, CC fields, and other communication labels.
ReviewedEvidence1 sourceSectionWriting & Style
Quick answer
Use c/o (“care of”) in an address when mail for the named recipient should be delivered through another person, organization, or address.
Key details
Core IssueThe abbreviation c/o means “care of” in an address and is used when a person can be reached through another person, organization, or address.
Phrase Roleformatting an address that routes correspondence through another recipient or location
Registergeneral to professional
Important caveats
Usage Boundary
Use c/o for routing correspondence through another person or place; it is not a synonym for CC, attention, or an email-copy instruction.
Further guidance
Address Format
Place c/o with the intermediary person or organization in the address block so the item can be routed to the intended recipient.
Meaning
c/o is the written abbreviation for “care of.”
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
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