Write a mailing address as name, street line, city state ZIP, then country line when needed, each on its own line.
Mail gets sorted by machines, then checked by humans when something looks odd. A clean layout keeps your letter out of the “mystery pile” and on the right truck. This page walks you through line order, what to put where, and the small details that stop returns and delays.
Mailing Address Lines At A Glance
Use the table as a quick layout map. Keep each line left aligned. Skip commas when you can; line breaks do the work.
| Line | What To Write | Notes |
|---|---|---|
| 1 | Recipient full name | Add a title only if it’s used in their mail. |
| 2 | Company or school name | Use a separate line for businesses, dorms, and campuses. |
| 3 | Attention or care of line | Use “ATTN” for a person or team, or “C/O” when someone receives mail for another. |
| 4 | Street number and street name | Keep directionals with the street line (N, S, E, W). |
| 5 | Apartment, suite, unit, or floor | Place it at the end of the street line when it fits. |
| 6 | P.O. Box or rural route line | Use this instead of a street line when the delivery point is a box or route. |
| 7 | City, state, ZIP or ZIP+4 | Use the two letter state code; ZIP+4 speeds sorting when you have it. |
| 8 | Country name | Use the full country name on the last line for international mail. |
How To Write Out Mailing Address Step By Step
If you searched “how to write out mailing address,” you’re usually trying to get one thing right: the delivery line order. Start with the recipient, then the delivery point, then the city line. Keep it plain and easy to scan.
Start With The Recipient Name
Put the person’s name on the first line. Use the name they’ll recognize from past mail. Middle initials are fine when you know them. Nicknames are fine when the person uses that name on bills and parcels.
Sending to a company? Put the person first, then the company line under it. If the business wants a department name, place it between the company line and the street line.
Use Attention, Care Of, And Mail Stops The Right Way
An attention line is for buildings where many people share one front desk, mailroom, or reception counter. Use “ATTN” plus a name or team. Keep it short.
“C/O” (care of) is for mail delivered to one person at another person’s location. Put the person who receives the mail on the C/O line, then list the street or box that actually gets delivery.
Some offices use internal routing such as a mail stop code. If a mailroom asks for one, place it on its own line above the street line, or follow the format they give you. Don’t invent a code.
Write The Street Line With Unit Details
The street line is where most errors happen. Put the street number first, then the street name, then the street type. Add unit details right after the street line when there’s room: “APT 4B” or “STE 210.” Skip the “#” symbol when you know the unit label.
US mail follows standard abbreviations for unit labels and street types. If you want the official rule set, see USPS Addressing Mailpieces. It lists the line order and the abbreviations that sorting gear expects.
If the unit does not fit on the street line, place it on the next line by itself. Keep the order the same: street first, unit second. Don’t swap them.
Build The City State ZIP Line
Write the city, then a space, then the state code, then a space, then the ZIP Code. Add ZIP+4 when you have it. The extra four digits can cut down on manual handling, especially in large buildings and dense areas.
Write this line in all caps if you want, yet mixed case still works as long as the letters are clear. What matters is clean spacing and no stray punctuation that looks like a character.
Check The Parts That Trigger Returns
Two missing pieces cause most “Return To Sender” marks: a unit number and a usable return block. If you’re mailing to a building with many doors, add the unit every time. If you’re mailing from a temporary place, write a return block that can take mail for the next few weeks. It’s worth the extra minute.
Writing Out A Mailing Address For Letters And Packages
Letters and parcels share the same destination layout, but packages add a few habits that save time. Keep the label flat and wrinkle free. Keep tape off printed text and barcodes.
Envelope Placement And Spacing
Place the destination block on the front, slightly right of center, with blank space around it. Put the return block in the top left. Keep both blocks away from the bottom edge where barcodes get printed during processing.
Use a dark pen. Avoid gel ink that smears. If you print labels, pick a font with clear zeros and ones. Skip script fonts for the destination block.
Packages Need A Contact Line
For parcels, a phone number can be useful when a carrier needs to schedule a pickup or confirm a gate code. Put the contact line near the return block, not in the middle of the destination block.
Dorms, Campuses, And Large Buildings
Schools and large campuses often route mail through a central room. Use the school name on its own line. Add the dorm name, building name, or box number on the next line if the school uses it.
If the school uses a student ID, place it after the name or on a separate line, based on what the mailroom asks for. A missing dorm or box detail can send the item on a tour of campus.
Military, Diplomatic, And Fleet Mailing
Military mail uses a special city line. The city is APO, FPO, or DPO. The state is AA, AE, or AP. The ZIP is a normal five digit ZIP or ZIP+4. Put the country name only when the label instructions for that carrier require it.
Keep the format clean and short. Put rank on the name line only when it’s part of the official name in the unit’s records. Put the unit and box info on the street line, then the APO/FPO/DPO city line under it.
Writing Out A Mailing Address For International Mail
International mail is the same basic stack of lines, with one twist: the country line is the sorting anchor. Put the country name alone on the last line, written in English when possible. Keep the destination postal code where that country expects it.
Use The Destination Country’s Line Order
Some countries place the postal code before the city. Some place a district name between city and street. If you can follow the local format, do it.
Postal operators share a standard set of elements and templates through the Universal Postal Union. The reference is UPU S42 International Addressing Standards. If you’re sending mail to a country with a format you’ve never used, that document shows where each element belongs.
Keep The Country Line Clean
Write the country name in full on the last line. Don’t use abbreviations like “USA” on outgoing international pieces. Don’t place the postal code on the country line.
Match Local Characters When You Can
If the destination uses a non-Latin script, you can add a second block in that script above the English block. Keep the final line in English with the country name so international sorting still works.
Clean Formatting Rules That Work Anywhere
These habits fit most carriers. They also make your mail readable to a neighbor who might forward it if it lands at the wrong box.
Use One Destination Block
Put the full destination block in one place on the front. Don’t repeat the destination on the back flap. Don’t place a second copy on the side unless the carrier asks for it.
Keep Spacing Steady
Use single spaces between words. Use one blank line only when you separate return and destination blocks. Avoid tight stacks where letters touch.
Pick Abbreviations And Stick With Them
Mixing “Apartment” on one line and “Apt.” on another won’t break delivery, yet it can slow matching in address databases. If you shorten, shorten the same way each time.
Match Online Form Fields To The Same Order
Web forms split the destination into fields. Fill them like you’d write the lines. Put apartment or suite data in the “Address Line 2” field, not in the notes box. Put the country in the country field, not on the street line.
If the form has a drop-down for state or province, use it. If it has a ZIP+4 box, add it when you know it. Then save the formatted view and compare it to the line order above.
Common Mistakes That Slow Delivery
Most delays come from missing unit data, swapped line order, or text that looks like a barcode. Fixing these takes minutes.
| Slip Up | What Goes Wrong | Fix |
|---|---|---|
| Unit number missing | Carrier can’t pick the right door | Add APT, STE, UNIT, or FL plus the unit value. |
| Street and PO Box both listed | Sorting picks the wrong delivery path | Use one delivery line that matches the delivery point. |
| City or ZIP doesn’t match | Item loops or routes out of area | Confirm the ZIP for that city and street. |
| Extra punctuation or symbols | Characters get misread by scanners | Drop commas, quotes, and emojis; stick to letters, numbers, spaces. |
| Street type missing | Street name collides with a similar one | Add ST, AVE, RD, BLVD, LN, DR, or the full word. |
| Illegible handwriting | Manual review slows processing | Print in block letters or use a printed label. |
| Country line missing | Outgoing mail stalls at export | Add the full country name on the last line. |
Copy Ready Templates
Use these as starting points. Replace the bracketed parts with real data. If you searched “how to write out mailing address” while filling an online form, the same order still applies.
US Street Address Template
[FULL NAME]
[STREET NUMBER] [STREET NAME] [STREET TYPE] [UNIT LABEL] [UNIT]
[CITY] [STATE] [ZIP] [ZIP+4]
US PO Box Template
[FULL NAME]
PO BOX [BOX NUMBER]
[CITY] [STATE] [ZIP]
International Template
[FULL NAME]
[HOUSE NUMBER] [STREET NAME]
[AREA OR DISTRICT]
[CITY] [POSTAL CODE]
[COUNTRY NAME]
Fast Self Check Before You Send
- Does the street line include a unit when the building has one?
- Is the city state ZIP line on one line, with clean spaces?
- Is the destination block away from the bottom edge?
- For overseas mail, is the country line last and written in full?
- Is the return block complete, so the item can come back if needed?