How HERE Determines the Postal City Name for a ZIP Code in the United States

Applies To
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HERE Map Data (Postal Area Zones)
HERE address and location datasets
Applications using ZIP code–based location data

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Summary
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For each ZIP code in the United States, HERE publishes one postal city name based on the default city defined by the United States Postal Service (USPS). Alternate city names may exist but are not used as the primary postal city in HERE map data.

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Answer
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HERE assigns a single postal city name to each ZIP code using the default city defined by the USPS.

This means:

Each ZIP code is associated with one official postal city name
Alternate or locally used city names are not published as the primary value

If you see a different city name than expected, it is typically because HERE follows the USPS “default city” designation.

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Symptoms
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Customers may observe:

A ZIP code mapped to a city name that differs from local or commonly used names
Missing alternate or neighborhood-level city names
Differences between HERE data and user expectations

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Root Cause
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### 1. USPS Standardization

The United States Postal Service assigns:

One default city name for each ZIP code

This name is used for:

Mail delivery
Official postal addressing

HERE uses this USPS-defined value as the postal city.

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### 2. One-to-Many Relationships

A single postal city may represent:
+ Multiple ZIP codes
A ZIP code may have:
+ Multiple recognized local city names
+ But only one designated default city

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### 3. Alternate Names Not Used as Primary

USPS may recognize:

Alternate city names
Abbreviations or common variations

However:

HERE publishes only the default city name
Alternate names are not included in the primary dataset

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Impact
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| Scenario | Impact |
| --- | --- |
| Using HERE ZIP code data | One standard city name returned |
| Comparing with local usage | Differences may appear |
| Searching by alternate names | May not match without enhancements |

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Solution / Recommended Actions
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### 1. Use Default Postal City for Standard Applications

Use HERE’s postal city value for:
+ Address validation
+ Postal compliance
+ Standardized datasets

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### 2. Use Alternate City Names for Search Enhancement

If your application requires:

Flexible search
User-friendly location input

You can use the Alternate City Names dataset, which provides:

Additional USPS-recognized names for ZIP codes
Common variations and synonyms

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### 3. Use Alternate Names as Synonyms Only

When using alternate names:

Use them for:
+ Search matching
+ Destination selection
Do NOT use them for:
+ Address uniqueness
+ Official display values

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Expected Behavior
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| Situation | Expected |
| --- | --- |
| ZIP code lookup | Returns one default city |
| Multiple local names exist | Only default is returned |
| Alternate names used | Only available via supplemental data |

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Notes
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HERE publishes postal city names based strictly on USPS definitions
Some ZIP codes:
+ Serve PO Boxes, buildings, or businesses only
+ May require additional data products for full coverage
Alternate city names are available as a separate dataset for enhanced use cases

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Related Information
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HERE Documentation: https://docs.here.com
HERE Developer Portal: https://platform.here.com/portal
HERE Support Portal: https://support.here.com

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Keywords
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postal city, ZIP code, USPS default city, postal area zone, alternate city names, HERE map data, address standardization