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Addressing Domestic Mail

There are many factors that affect the efficiency of mail delivery, but the most common cause of a delay in delivery is improper addressing. By following a few simple rules, you can eliminate needless delays.

The Mail Services and the Postal Service read addresses from the bottom up. If an address has both a street address and a Post Office Box, the U.S. Postal Service will deliver to the address closest to the bottom.

On mail addressed to locations within the United States, the bottom line should contain the city, state and Zip Code + 4. To find the right zip code, use the USPS lookup.

There should be only one address label on each package. Remove or black out any old addresses.

The Postal Service has automated letter sorting equipment which uses an Optical Character Reader (OCR) to electronically read the address and print a bar code on your letter. The bar code allows high-speed sorting machines to route your letter rapidly. By placing your address within the designated area, the OCR can read the address. The OCR can only read the address if it is written by machine or typewriter. It is requested that all addresses be printed in capital letters without punctuation for accurate OCR reading. The guidelines which follow are encouraged by the U.S. Postal Service but are not required. OCR processed mail may be delivered more quickly and accurately than manually processed mail.

All mail except inter-departmental mail must have a return address. There are many ways that return addresses are written on campus, but there is only one way that will receive the highest level of service from the U.S. Postal Service and the Mail Services:

Any other format may result in a delay. It is important to note the line "ONE SHIELDS AVENUE" and its placement directly above the bottom line "DAVIS, CA 95616-XXXX." This is the equivalent of our street address. Mail addressed this way will be delivered directly to the university from the Sacramento Sectional Center Facility. If any other line is second from the bottom, the mail will be delivered first to the Davis Post Office where it is forwarded to the Mail Services. This typically results in a one day delay in delivery.

Include your ID number in the return address. All outbound Postal Service and United Parcel Service mail must include a valid 4-digit account number that has been approved by the Mail Services. It is preferred that this account number be adjacent to the department name in the return address. This information is needed so that the Mail Services can accurately charge for postage and services.

UCDMC return address. The UCD Medical Center has many units in and around the Hospital complex. Many of these units have separate street addresses; however, all units at the Medical Center can have mail returned with the following address:

For most addresses there is a 4-digit extension that goes with the standard 5-digit zip code. The Postal Service calls this expanded number Zip+4. By including the Zip+4 number in addresses, the Postal Service can process mail more efficiently. You can find the full zip code for any address on the USPS Zip Code Lookup.

It is always preferable to address mail so that the longest side remains horizontal. In some cases, the U.S. Postal Service will add a surcharge to mail that has the longest side vertical. Unless you are using an address label, the return address should be in the upper left corner and the address should be below and to the right of the return address.

See also Preparing Letters & Flats or Preparing Packages/Parcels.