Magento – Not saved tax vat field entered in checkout page in magento

customer-addressmagento-1.7magento-1.8

Customer Address in Admin Page:

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In my checkout page,

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Filled the fields and I placed the order,

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After placed an order I checked in my backend,all the fields are saved correctly except taxvat field.

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Best Answer

Override core module Mage_Checkout_Model_Type_Onepage In onepage.php file,

 public function saveBilling($data, $customerAddressId)
 {

After this,

 $address->implodeStreetAddress();

Add the line,

 $address->setVatId($data['taxvat']);  

 }