Magento2 How to add customer attribute

Magento 2.3 introduces the new way to modify data using Data and schema patches.

To add customer attribute we will implement \Magento\Framework\Setup\Patch\DataPatchInterface.

Create a class CustomerCustomAttributePatcher in your module Setup directory: Vendor\Module\Setup\Patch\Data\CustomerCustomAttributePatcher

<?php
namespace Vendor\Module\Setup\Patch\Data;

use Magento\Eav\Model\Config;
use Magento\Eav\Setup\EavSetupFactory;
use Magento\Framework\Setup\Patch\DataPatchInterface;
use Magento\Eav\Model\Entity\Attribute\SetFactory as AttributeSetFactory;

class CustomerCustomAttributePatcher implements DataPatchInterface
{
    /**
     * @var Config
     */
    private Config $eavConfig;

    /**
     * @var EavSetupFactory
     */
    private EavSetupFactory $eavSetupFactory;

    /**
     * @var AttributeSetFactory
     */
    private AttributeSetFactory $attributeSetFactory;

    /**
     * @param Config $eavConfig
     * @param EavSetupFactory $eavSetupFactory
     * @param AttributeSetFactory $attributeSetFactory
     */
    public function __construct(
        Config $eavConfig,
        EavSetupFactory $eavSetupFactory,
        AttributeSetFactory $attributeSetFactory
    ) {
        $this->eavConfig = $eavConfig;
        $this->eavSetupFactory = $eavSetupFactory;
        $this->attributeSetFactory = $attributeSetFactory;
    }

    public function apply()
    {
        $eavSetup = $this->eavSetupFactory->create();

        $customerEntity = $this->eavConfig->getEntityType(\Magento\Customer\Model\Customer::ENTITY);
        $attributesetId = $customerEntity->getDefaultAttributeSetId();

        $attributeset = $this->attributeSetFactory->create();
        $attributeGroupId = $attributeset->getDefaultGroupId($attributesetId);

        $eavSetup->addAttribute(\Magento\Customer\Model\Customer::ENTITY, 'custom_attr', [
            'type' => 'int',
            'input' => 'text',
            'label' => 'Customer custom Attribute',
            'required' => false,
            'default' => 0,
            'visible' => false,
            'user_defined' => true,
            'system' => false,
            'is_visible_in_grid' => true,
            'is_used_in_grid' => true,
            'is_filterable_in_grid' => true,
            'is_searchable_in_grid' => true,
            'position' => 50,
            'sort_order' => 50,
            'note' => 'Customer custom Attribute'
        ]);

        $customerAttribute = $this->eavConfig->getAttribute(\Magento\Customer\Model\Customer::ENTITY, 'custom_attr');

        $customerAttribute->addData([
            'attribute_set_id' => $attributesetId,
            'attribute_group_id' => $attributeGroupId,
            'used_in_forms' => ['adminhtml_customer', 'customer_account_edit']
        ]);
        $customerAttribute->save();
    }

    public static function getDependencies()
    {
        return [];
    }

    public function getAliases()
    {
        return [];
    }
}

For multiple patches or adding multiple attributes:

• All classes must be under same Setup\Patch\Data directory.
• Must implement Magento\Framework\Setup\Patch\DataPatchInterface interface.