How to Apply a Recursive BOGO Rule for the Same Product in WooCommerce?

Implementing a Recursive BOGO Rule in WooCommerce is the perfect solution! This dynamic promotion encourages customers to buy more by offering a “Buy One, Get One” deal that scales with their order. Customers end up buying more quantities to maximize the benefits of these promotions.

Solution: Apply a Recursive BOGO Rule for the Same Product in WooCommerce

The code snippet applies a recursive “Buy One, Get One” discount rule for a specific product in the WooCommerce cart. For example, purchase 2 items and get 1 free; buy 4 items and receive 2 free, and so on. If the customer adds more items with an even quantity, the free product is added through the same process in a recursive manner.

add_action('woocommerce_cart_calculate_fees', 'ts_custom_discount', 10, 1);

function ts_custom_discount($cart)
{
    if (is_admin() && !defined('DOING_AJAX')) return;

    // YOUR SETTINGS:
    $targeted_product_id = 54; // Set HERE your targeted product ID

    // Initializing variables
    $discount = $qty_notice = 0;
    $parent_prices = array();

    // Loop through cart items
    foreach ($cart->get_cart() as $key => $cart_item) {
        if (in_array($targeted_product_id, [$cart_item['product_id'], $cart_item['variation_id']])) {
            $quantity = (int) $cart_item['quantity'];
            $qty_notice += $quantity;

            // Collect the price of the parent product
            $parent_prices[] = floatval($cart_item['data']->get_price());
        }
    }

    // Check if the quantity is a multiple of 2 (even)
    if ($qty_notice % 2 == 0) {
        // Calculate the number of free items
        $free_items = $qty_notice / 2;

        // Apply discount based on the number of free items
        $discount -= $free_items * floatval($parent_prices[0]);
    }

    // Applying the discount
    if ($discount != 0) {
        $cart->add_fee('Custom Discount', $discount, true);

        // Displaying a custom notice (optional)
        wc_clear_notices(); // clear other notices on the checkout page.
        if (!is_checkout()) {
            wc_add_notice(__("Buy One get One discount Applied."), 'notice');
        }
    }
    // Display a custom notice on the cart page when quantity is not enough
    elseif ($qty_notice > 0 && $qty_notice % 2 != 0) {
        wc_clear_notices(); // clear other notices on the checkout page.
        if (is_cart()) {
            wc_add_notice(__("Add more items to get the BOGO Offer."), 'notice');
        }
    }
}

This to the shop owners who are running or planning to run BOGO offers on their WooCommerce store…

BOGO deals are great for increasing your sales, but have you thought about which offers are bringing you more revenue and which offers are not performing that great?

Don’t just set a BOGO deal, track the revenue generated by your deals in real-time with the Flexi BOGO for WooCommerce plugin.

Explore Flexi BOGO

Output

When the customer adds products to the cart, the code loops through each item in the cart to identify the targeted product and adds a free product for every even quantity. If the customer adds 6 items, the code calculates 6/2=3 free items and applies a full discount for 3 items of the product.

Similarly, you can also automatically add free product for more number of categories. Check out this guide that will help you to automatically add a product to your WooCommerce cart based on ‘N’ number of conditions.