How to Write an Apartment Address Perfectly

If you've never lived in (or sent mail to) an apartment before, you might not know how to write an address with an apartment number. Use these tips to write a perfectly formatted mailing address for apartments.

If you're unclear about general guidelines for writing addresses, start with this helpful video from the US Postal Service:

How to Write an Apartment Address

The Essential Apartment Address Formula

Here is the quick & easy way to write an apartment address perfectly. If you need more step-by-step instructions, keep scrolling.

1. Write the recipient's full legal name on the first line.
2. Write the street number, name, and apartment unit (with the APT abbreviation) on the second line Example: 123 Main St, Apt 2
3. On line three, write the state, city and zip code, including the 4 digits at the end if you know them. Example: New York, NY 11111

How to Use "Apt" in an Apartment Address

"Apt" is a common abbreviation for an apartment that is always acceptable when you write an address. It goes on the second line next to the street number and name. You can also write out "Apartment," but abbreviations are actually preferable, which we explain below in more detail.

Many people place the apartment number on the third line, and include the city and state/province on a fourth line, but this is not technically correct. However, you will usually receive your mail if your address is written this way. You can also utilize the third line if you're short on space in the second.

Should I Put the Apartment Number Below the Street Number?

Your apartment number should go next to the street number and name. The third line actually has another purpose, but most people don't use it that way. The USPS says people should reserve the second line for special designators like "care of" or special handling instructions. For example:

Jane Doe

123 Main St, Bldg E, Apt 2

c/o John Doe

New York, NY 11111

Want more reassurance that you're on the right track? Check out this great video directly from USPS on writing addresses correctly:

How to Write Abbreviations in Any Address

Abbreviating common words actually helps the postal service manage mail more easily. Abbreviations such as BLDG for building or APT for apartment are called “secondary address designators," and they are standardized. That's why you must be careful not format abbreviations incorrectly, as doing so can delay your mail and packages. You do not need to include a period after these abbreviations (though doing so in unlikely to delay your mail).

Here are some of the most common secondary address designators for the US postal service:

In the case of "Unit," there is no abbreviation. However, it still serves as a critical address designator.

Less Common Abbreviations

• Basement – BSMT
• Front – FRNT
• Lobby – LBBY
• Hanger – HNGR
• Slip – SLIP
• Lot – LOT
• Pier – PIER
• Rear – REAR
• Side – SIDE
• Front – FRNT
• Lower – LOWR
• Space – SPC
• Trailer – TRLR
• Key – KEY
• Office – OFC
• Space – SPC

International Apartment Addresses

Different countries have different address layouts. Research the recipient's country and write the address in the local format. This typically involves putting the recipient's name on the first line, followed by building/apartment number, street, city/town, state/province (if applicable), postal code, and country name written in ALL CAPS.

Always write the address in the recipient's local language. This ensures clarity and avoids potential misreadings. Avoid abbreviating street types (St., Ave., Blvd.), directions (N., S., E., W.), or state/province names unless you're sure it's the local convention. Spell out the country name in ALL CAPS on the last line.

Finally, get the right postal code and write it correctly. Missing or wrong codes can significantly delay delivery.

Step-By-Step Instructions for Writing an Apartment Address

1. Place Your Delivery Address In the Center of Your Mail

Placing the delivery address in the center of your mail is standard. This is the location mail sorters and carriers look to. To avoid any confusion, always center the delivery address on your mail.

Apartment Address Tip: Ideally you want to use as few lines as possible for the delivery address.

2. Begin with the Full Name of the Recipient

Make sure to use the recipient's legal name before writing an apartment address. Mail and packages might not arrive to the recipient if you use a nickname that isn't associated with their apartment address.

For example:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111

Apartment Address Tip: Using legal names for apartment addresses is also wise, as they’ll send any forwarded mail to the correct location.

3. Write the Street Name and Number on the Second Line

If you talk with USPS, they'll tell you that using multiple address lines for writing an address with an apartment number is incorrect. The street number, apartment address, and apartment number go on the second line.

For example:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111

Apartment Address Tip: Remember to add a comma after the street address when you address a letter to an apartment.

4. Write the Apartment Unit Number on the Second Line

Keep your apartment unit number on the same line as the building and street name:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111

5. Write the City, State/Province, and ZIP Code on the Third Line

The general standard is to wrap an address line with similar components. So, for example, your name should all be on one line with your street name on another.

The last line should always include your city, state, and ZIP code.

For example:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111

Apartment Address Tip: You should only drop down to an additional line and put your building or apartment number there if you are short on space.

6. Add Recipient’s Country If Shipping Internationally

If you’re wondering how to write a letter to an apartment overseas, it’s simple - just add the country after the ZIP code. You don’t have to include the country for domestic mail.

For example:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111, USA

Apartment Address Tip: It’s redundant to write the same country for the recipient and return address. Save yourself time and space and skip it unless you need it!

7. Remember to Write Your Return Address

Now, it’s time to focus on your return address. Place your return address in the top left corner of your mail and follow the same apartment address example.

For example:

John Smith

456 Ocean Ave, Bldg A, Apt 9

Los Angeles, CA 90001

Apartment Address Tip: Follow the same formatting for your recipient’s apartment number for your return address.

8. Add Postage Based on Rates

The last step is to make sure you have the correct amount of postage based on current rates. Again, you can stop by your local USPS to ensure you have the correct amount before mailing it off.

Apartment Address Tip: Skip the line and check online for the most updated mailing and shipping prices.

Common Mistakes When Writing an Apartment Address

Now that you know how to format apartment address details for mail, it’s important to address some common mistakes.

Using Commas and/or Periods in the Wrong Place

Avoid using any commas or periods unnecessarily in unit addresses. You should only use these punctuation marks when separating building and unit numbers for both recipients and return addresses.

For example:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111

Including City and Street Abbreviations

Avoid shorthand, including abbreviations, for any city or street names. You should use abbreviations for words like "street," "apartment," and "building," as we'll cover below.

Forgetting Neat Handwriting

Remember your mail carrier needs to be able to read your writing to ensure proper delivery. Take the time to write neatly, or consider printing a label as an alternative option.

Inserting the Wrong ZIP Code

If you learn how to write a letter to an apartment but put in the wrong ZIP code, it won’t be delivered properly. Pay close attention to these numbers to get them right the first time.

Not Including Common Abbreviations like "Apt" or "Bldg"

While you should not abbreviate specific names like street names or cities, you can and should use common abbreviations for words like "apartment," "building," and "floor." These abbreviations save space on your envelope, making it easier and quicker to read your address. Here's a list of the abbreviations you should use:

What Happens if You Write an Address Incorrectly?

In the worst case scenario, an address written incorrectly will simply not arrive at its destination, and instead will be returned to the sender. In some cases, USPS will still be able to deliver the package even if the address is slightly incorrect. However, making sure you include all the elements we mentioned above, and ensuring you have the sender's proper legal name will go a long way toward preventing mistakes and delays.

And, don’t forget, if you ever need to file a claim for package theft, your new skill will come in handy. These are enough reasons to master the art of the apartment address format!

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Apartment Address FAQs

What Happens if You Don’t Put the Apartment Number on the Envelope?

If you don’t include the apartment number on the envelope, the mail carrier won’t know which mailbox to deliver it to. In this case, the mail will likely be returned to the sender.

How Do You Write an Address That Has Both a Building and Apartment Number?

You can add the building number before the apartment number, if it’s included in the address.

For example:

Jane Doe

123 Main St, Bldg E, Apt 2

New York, NY 11111

How Do You Write the Floor Number in an Address?

A floor number in an apartment address will come before the unit number.

For example:

Jane Doe

123 Main St, Fl 1, Apt 2

New York, NY 11111

What If My Mailing Address Zip Code is Different From My Physical Address?

If you live on the border of a town or county, your physical address and mailing address may have different zip codes. Defer to the mailing address when sending or receiving letters or packages. The postal service offers zip code lookup if you need the zip code for your mailing address.