Key takeaways
- Use STE followed by the suite identifier
- Place the suite at the end of the delivery line when space allows
- Keep company, attention, department, and suite as different concepts
- Preserve suite identifiers as text and include them in shipping labels
Authorship and review
Read our editorial and review principles- Written by
- Random Address Generator Editorial Team
- Reviewed by
- US Business Address Review Team
- Latest substantive update
- Published a US suite-address guide for business mail, forms, departments, and label output.
How to write a suite in a US address
For mailing output, USPS recognizes STE as the standard suite designator. Put it after the street address when the complete line fits. The city, two-letter state abbreviation, and ZIP Code follow on the last line.
The suite is not decoration. In a large office building, it distinguishes one delivery point from many others sharing the same street address.
Suite, department, floor, and attention line are not synonyms
A suite identifies space inside a property. A department identifies a part of the organization. A floor identifies a building level. An attention line names the person or team expected to handle the item. Combining all four into Suite creates data that cannot be printed or searched reliably.
Keep these fields separate in business systems, even if a small form initially renders only company, recipient, street, and optional secondary line.
| Element | Example | Meaning |
|---|---|---|
| Company | Northstar Labs | Organization receiving mail |
| Attention | Attn: Jordan Lee | Person or team handling it |
| Department | Accounts Payable | Internal organizational unit |
| Floor | FL 5 | Building level |
| Suite | STE 501 | Specific occupied space |
When the company address needs another line
If the suite makes the delivery line too long, move the complete secondary detail immediately above the street line. Do not split STE from its identifier. USPS business-address guidance also preserves the relative order of firm, attention, and delivery information when lines are removed or wrapped.
A database should not inherit a label printer's width limit. Store full values, then apply formatting rules for each output size.
Suite numbers in checkout and CRM forms
A single optional unit field can accept apartment, suite, floor, and room values for consumer checkout. A CRM or shipping system may need a unit-type selector and separate unit value. Choose based on what the application actually does after collection.
Do not accept the suite in one screen and omit it from confirmation emails, labels, exports, or carrier requests. That is a common integration bug because the secondary line is nullable and easy to forget.
- Store suite values as text
- Keep company name outside the street line
- Include secondary details in deduplication carefully
- Test exports and printed labels, not just database inserts
- Do not use a suite as evidence that a business occupies the address
Business-address cases worth testing
Use cases that expose field loss: a company with no named recipient, a long department plus suite, a suite containing letters, and two tenants at the same street. Also test a user who types Suite 501 in Line 1 and leaves Line 2 blank; normalization should not duplicate the suite.
Keep fixtures synthetic or based on authorized public non-residential locations. A correct suite shape does not prove a company or person is present.
Frequently asked questions
How do you write a suite number in an address?
Use STE followed by the suite identifier, preferably at the end of the street delivery line when it fits.
Does suite go before or after the street address?
It normally follows the street on the same delivery line. If the line is too long, place the complete suite line immediately above the street.
Is a suite the same as a department?
No. A suite identifies space in a building; a department identifies an organizational unit.
Can a suite number contain letters?
Yes. Store it as text so values such as 5A or PH-B are preserved.