# Assign additional field

Use the **addSubscriptionAdditionalInformationField** method to assign an additional information field to a subscription.

## Requirements

The maximum number of additional information fields that can be added on a subscription is 5, while the maximum field length is 100 characters.

## Request parameters

<table><thead><tr><th width="214">Parameter</th><th>Type / Description</th></tr></thead><tbody><tr><td><code>sessionID</code></td><td><p><strong>Required (string)</strong></p><p>Session identifier, the output of the <strong>Login</strong> method. Include <code>sessionID</code> into all your requests. 2Checkout throws an exception if the values are incorrect. The <code>sessionID</code> expires in <strong>10 minutes</strong>.</p></td></tr><tr><td><code>SubscriptionReference</code></td><td><p><strong>Required (string)</strong></p><p>Unique, system-generated subscription identifier.</p></td></tr><tr><td><code>fieldName</code></td><td><p><strong>Required (string)</strong></p><p>The name of the additional information field. Used for identifying additional information fields.</p></td></tr><tr><td><code>fieldValue</code></td><td><p><strong>Required (string)</strong></p><p>The value of the additional information field.</p></td></tr></tbody></table>

### Request sample

```php
<?php

require('PATH_TO_AUTH');

$subscriptionReference = 'F27CFE06ED';
$fieldName = 'subscription';
$fieldValue = 'test';
try {
    $subscriptionInfo = $client->addSubscriptionAdditionalInformationField($sessionID, $subscriptionReference, $fieldName, $fieldValue);
}
catch (SoapFault $e) {
    echo "subscriptionInfo: " . $e->getMessage();
    exit;
}
var_dump("subscriptionInfo", $subscriptionInfo);
```

## Response parameters

<table><thead><tr><th width="313.199951171875">Parameter</th><th>Type / Description</th></tr></thead><tbody><tr><td><code>AdditionalSubscriptionInformation</code></td><td><p><strong>Object</strong></p><p>Contains information related to the additional information field.</p></td></tr><tr><td><code>fieldName</code></td><td><p><strong>String</strong></p><p>The name of the additional information field. Used for identifying additional information fields.</p></td></tr><tr><td><code>fieldValue</code></td><td><p><strong>String</strong></p><p>The value of the additional information field.</p></td></tr></tbody></table>


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```
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```

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