How to Parse US Addresses in PHP / Laravel

What the API returns

Every response is wrapped in a standard envelope. For parsing, the Result field is a single object whose properties are the address components. This is a real response for 1600 Pennsylvania Ave NW Apt 4B:

{
  "Id": "2737f8f3-af83-4ba1-b9c3-e29d2ba9e03b",
  "Result": {
    "inputAddress": "1600 Pennsylvania Ave NW Apt 4B Washington DC 20500",
    "addressLine1": "1600 PENNSYLVANIA AVE NW",
    "addressLine2": null,
    "addressNumber": "1600",
    "streetPreDir": "",
    "streetName": "PENNSYLVANIA",
    "streetPostType": "AVE",
    "streetPostDir": "NW",
    "unitType": "apt",
    "unitNumber": "4b",
    "city": "WASHINGTON",
    "stateCode": "DC",
    "zipCode": "20500",
    "zip4": null,
    "county": null,
    "matchMode": "Speculative",
    "matchTier": "Near",
    "confidence": 0.7,
    "matchCode": {
      "houseNumber": "Matched",
      "street": "Matched",
      "unit": "Matched",
      "city": "Matched",
      "state": "Matched",
      "zipCode": "Matched",
      "zip4": "NotApplicable"
    },
    "footnotes": ["recovered: standardized via correction, not an exact match"]
  },
  "ClientSessionId": null,
  "StatusCode": 200,
  "IsError": false,
  "Errors": []
}

The fields you'll use most often are covered in the component map below. Note that some fields are empty or null when they don't apply - there's no leading directional here, so streetPreDir is an empty string, and the parser didn't append a zip4 or county, so those are null.

Get your API key

1. Sign up at sthan.io and subscribe to the free Address Parser tier
2. Open your dashboard and create an API key
3. Copy the key - it looks like sthan_live_xxxxxxxxxxxxxxxx

You get the key immediately, with no approval queue. An API key is the simplest way to authenticate: you send it as a Bearer token on every request and there is no separate login step. (If you prefer a short-lived token, there is a JWT flow covered later.)

Configure the project

Keep your key out of source control by reading it from .env. Add the key to .env and surface it through a config entry:

# .env  (never commit this file)
STHAN_API_KEY=sthan_live_xxxxxxxxxxxxxxxx

<?php
// config/services.php
return [
    // ...existing services...

    'sthan' => [
        'key' => env('STHAN_API_KEY'),
        'base_url' => 'https://api.sthan.io',
    ],
];

Build the parser client

Wrap the call in a small service class. Laravel's Http client URL-encodes nothing for you in the path, so encode the address yourself, call the endpoint, unwrap the envelope, and return the Result array:

<?php

namespace App\Services;

use Illuminate\Support\Facades\Http;
use RuntimeException;

class AddressParser
{
    public function parse(string $address, string $mode = 'speculative'): array
    {
        $base = config('services.sthan.base_url');

        $envelope = Http::withToken(config('services.sthan.key'))
            ->timeout(10)
            ->get($base . '/v2/address-parser/usa/' . rawurlencode(trim($address)), [
                'match' => $mode,
            ])
            ->throw()          // raise on 4xx/5xx
            ->json();

        if ($envelope['IsError'] ?? false) {
            throw new RuntimeException(implode(', ', $envelope['Errors'] ?? []));
        }

        return $envelope['Result'];
    }
}

That's the whole integration. One call:

$parser = new \App\Services\AddressParser();
$result = $parser->parse('1600 pennsylvania ave nw apt 4b washington dc 20500');

echo $result['addressNumber'];   // 1600
echo $result['streetName'];      // PENNSYLVANIA
echo $result['streetPostType'];  // AVE
echo $result['unitType'] . ' ' . $result['unitNumber'];          // apt 4b
echo "{$result['city']} {$result['stateCode']} {$result['zipCode']}";  // WASHINGTON DC 20500

Choose a match mode

The match parameter controls how much typo tolerance the parser applies while standardizing components. The same call supports four modes, from strictest to loosest:

If you omit match, the endpoint defaults to speculative for the widest recovery. Whichever mode you pick, the location-defining parts of the address - the primary number, ordinal, directional, state, and the street's core name - are never substituted. A looser mode only widens tolerance for misspellings of the same street.

Map the components to your fields

Each component comes back as its own field, so mapping them to database columns is a direct copy. The fields you'll use most:

A few more components cover edge cases: streetPreType, streetPreMod, streetPreSep, and streetPostMod capture pre/post modifiers in unusual street names (for example "Avenue of the Americas"). They're empty for ordinary addresses. Pair the parse with matchCode - a per-component breakdown (Matched / Corrected / Inferred / Unmatched / NotApplicable) - so you can tell which fields were trusted as-is versus corrected. Here is a controller turning a parse straight into structured columns:

<?php

namespace App\Http\Controllers;

use App\Models\Address;
use App\Services\AddressParser;
use Illuminate\Http\Request;

class AddressController extends Controller
{
    public function __construct(private AddressParser $parser) {}

    public function store(Request $request)
    {
        $result = $this->parser->parse($request->input('address'));

        // One column per component — ready for Eloquent
        $address = Address::create([
            'address_number'  => $result['addressNumber'],
            'street_pre_dir'  => $result['streetPreDir'],
            'street_name'     => $result['streetName'],
            'street_type'     => $result['streetPostType'],
            'street_post_dir' => $result['streetPostDir'],
            'unit_type'       => $result['unitType'],
            'unit_number'     => $result['unitNumber'],
            'city'            => $result['city'],
            'state'           => $result['stateCode'],
            'zip_code'        => $result['zipCode'],
            'zip4'            => $result['zip4'],
        ]);

        return response()->json($address, 201);
    }
}

Alternative: JWT authentication

An API key is the simplest option and is all most apps need. If your security policy prefers short-lived credentials, the platform also supports a 2-step JWT flow. You call GET /Auth/Token once with your profileName and profilePassword headers, receive a token valid for up to 60 minutes, then send that token as the Bearer value on subsequent calls:

use Illuminate\Support\Facades\Http;

function sthan_token(): string
{
    $envelope = Http::withHeaders([
            'profileName'     => env('STHAN_PROFILE_NAME'),
            'profilePassword' => env('STHAN_PROFILE_PASSWORD'),
        ])
        ->get('https://api.sthan.io/Auth/Token')
        ->throw()
        ->json();

    return $envelope['Result']['access_token'];
}

// Then send the cached token as the Bearer value
$result = Http::withToken(sthan_token())
    ->get('https://api.sthan.io/v2/address-parser/usa/' . rawurlencode($address), [
        'match' => 'speculative',
    ])
    ->json();

Everything else - the endpoint, the envelope, the parsing - stays exactly the same. Cache the token (for example in Cache::remember()) and refresh it shortly before the 60-minute expiry rather than fetching one per request.

Handle errors

Two status codes are worth handling explicitly so a hiccup never stalls a batch job:

• 401 - The key or token was rejected. Check the value and, on the JWT flow, refresh and retry once.
• 429 - Rate limit reached. Back off and retry rather than dropping the row.

use Illuminate\Http\Client\RequestException;

$response = Http::withToken(config('services.sthan.key'))
    // Retry up to twice, 1s then 2s apart, but only on a 429
    ->retry(2, 1000, function ($exception) {
        return optional($exception->response)->status() === 429;
    }, throw: false)
    ->get('https://api.sthan.io/v2/address-parser/usa/' . rawurlencode($address), [
        'match' => 'speculative',
    ]);

if ($response->status() === 401) {
    // Key or token rejected — check the value, don't retry blindly
}

$result = $response->json('Result');

The exponential back-off (1s, then 2s) is enough for transient limits. For a large backfill, add a small delay between rows and a circuit breaker so one bad minute doesn't stall the whole queue.

What's next: confirm the parsed address is deliverable

Parsing gives you clean, structured components fast. It does not, on its own, confirm that mail or a package will actually arrive - a well-formed address can still point at a unit that no longer accepts delivery. When deliverability matters, run the address through the Address Verification API, which returns a deliverability status and appends ZIP+4 and county. It's the same envelope and the same Http client pattern - one GET against /v2/address-verification/usa/{address}. The PHP / Laravel walkthrough is here: Verify US Addresses in PHP / Laravel.

If you want users to enter a clean address in the first place, Address Autocomplete suggests complete addresses as they type. Pair autocomplete (as they type) with parsing and verification (at submit) to keep your address data clean end to end.