C/O stands for “care of” and tells a carrier to deliver a package or letter through an intermediary, someone other than the final recipient. You’ll see it on shipping labels when the recipient can’t receive mail at their own address and needs another person, business, or location to accept it on their behalf.
How “Care Of” Works
When you write “c/o” on a package, you’re telling the shipping carrier that the person named on the first line doesn’t directly receive mail at that address. The name after “c/o” is the party responsible for making sure the item reaches the intended recipient. Think of it as adding a trusted middleman to the delivery chain.
For example, if you’re shipping a birthday gift to your friend Sarah, but she’s staying at her parents’ house for the summer, you’d address the package to Sarah “c/o” her parents. The carrier delivers to the parents’ address, and because the package is marked care of them, they know to hold it for Sarah.
When You’d Use C/O on a Shipment
The most common scenarios fall into a few categories:
- Someone staying at another person’s home. The recipient is temporarily living with a friend, relative, or host and doesn’t have their own mailbox at that address.
- Shipping to a workplace. You want a package delivered to someone at their office. Writing c/o before the company name tells the mailroom or front desk that the package belongs to the person listed above it.
- Hotels, hospitals, and dorms. If someone is staying temporarily at a facility, addressing the package c/o that location signals the front desk or mail staff to hold it for a specific guest, patient, or resident.
- Legal or business agents. Companies often receive official documents through a registered agent. Individuals might route sensitive paperwork through an attorney’s office. In both cases, c/o directs the delivery through the agent’s address.
The thread connecting all of these: the recipient doesn’t normally get mail at that address, so you need to tell the carrier who at that location should accept the package.
How to Format a C/O Address
The layout is straightforward. The recipient’s name always goes on the first line. “C/O” and the intermediary go on the second line. The street address, city, state, and ZIP code follow as normal.
If you’re shipping to someone at a business:
Jane Smith
C/O Greenfield Marketing
742 Oak Avenue
Austin, TX 78701
If you’re routing a package through a specific person at that business (say you trust a particular employee to hand it off), you can name that person on the c/o line and put the company on the third line:
Jane Smith
C/O Tom Rivera
Greenfield Marketing
742 Oak Avenue
Austin, TX 78701
For a personal residence, it works the same way. If Jane is staying with her aunt:
Jane Smith
C/O Margaret Smith
309 Pine Street
Denver, CO 80202
Capitalize “C/O” on the label for clarity. Most carriers and mail sorting systems recognize both “C/O” and “c/o,” but keeping it uppercase and on its own line helps avoid confusion.
C/O for Important or Sensitive Packages
When you’re shipping documents that are time-sensitive or valuable, using c/o with a named individual adds a layer of accountability. Instead of sending a contract to a large law firm’s general address and hoping it reaches the right desk, you write c/o followed by the name of the specific attorney or assistant handling your case. That person becomes responsible for getting the package to you or processing it on your behalf.
This is especially useful for legal filings, tax documents, or anything requiring a signature. Naming a trusted individual on the c/o line reduces the chance of the package sitting unclaimed in a mailroom or being opened by the wrong person.
Does C/O Work With All Carriers?
Yes. USPS, UPS, FedEx, and DHL all recognize c/o addresses. The notation doesn’t change how the carrier routes or delivers the package. It still goes to the physical address listed. The c/o line simply identifies who at that address should receive it. Carriers deliver to addresses, not names, so the package arrives at the street location regardless. The c/o instruction matters most once the package is at the door or in the mailroom, telling whoever accepts it that the item belongs to a specific person.
One thing to keep in mind: if you’re shipping to a hotel or hospital, call ahead to confirm they accept packages for guests or patients. Some facilities have policies about holding deliveries, and knowing their process helps you format the address correctly. Many hotels, for instance, want the guest’s name, c/o the hotel name, with a note of the check-in date or room number.