woocommerce/templates/checkout/form-shipping.php

<?php
/**
 * Checkout shipping information form
 *
 * @author 		WooThemes
 * @package 	WooCommerce/Templates
 * @version     2.1.2
 */

if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly
?>
<div class="woocommerce-shipping-fields">
	<?php if ( WC()->cart->needs_shipping_address() === true ) : ?>

		<?php
			if ( empty( $_POST ) ) {

				$ship_to_different_address = get_option( 'woocommerce_ship_to_billing' ) == 'no' ? 1 : 0;
				$ship_to_different_address = apply_filters( 'woocommerce_ship_to_different_address_checked', $ship_to_different_address );

			} else {

				$ship_to_different_address = $checkout->get_value( 'ship_to_different_address' );

			}
		?>

		<h3 id="ship-to-different-address">
			<label for="ship-to-different-address-checkbox" class="checkbox"><?php _e( 'Ship to a different address?', 'woocommerce' ); ?></label>
			<input id="ship-to-different-address-checkbox" class="input-checkbox" <?php checked( $ship_to_different_address, 1 ); ?> type="checkbox" name="ship_to_different_address" value="1" />
		</h3>

		<div class="shipping_address">

			<?php do_action( 'woocommerce_before_checkout_shipping_form', $checkout ); ?>

			<?php foreach ( $checkout->checkout_fields['shipping'] as $key => $field ) : ?>

				<?php woocommerce_form_field( $key, $field, $checkout->get_value( $key ) ); ?>

			<?php endforeach; ?>

			<?php do_action( 'woocommerce_after_checkout_shipping_form', $checkout ); ?>

		</div>

	<?php endif; ?>

	<?php do_action( 'woocommerce_before_order_notes', $checkout ); ?>

	<?php if ( apply_filters( 'woocommerce_enable_order_notes_field', get_option( 'woocommerce_enable_order_comments', 'yes' ) === 'yes' ) ) : ?>

		<?php if ( ! WC()->cart->needs_shipping() || WC()->cart->ship_to_billing_address_only() ) : ?>

			<h3><?php _e( 'Additional Information', 'woocommerce' ); ?></h3>

		<?php endif; ?>

		<?php foreach ( $checkout->checkout_fields['order'] as $key => $field ) : ?>

			<?php woocommerce_form_field( $key, $field, $checkout->get_value( $key ) ); ?>

		<?php endforeach; ?>

	<?php endif; ?>

	<?php do_action( 'woocommerce_after_order_notes', $checkout ); ?>
</div>