Offer discounted product if order quantity below x number in woocommerce cart

This code displays a message on the cart page to entice customers to buy more products if their cart quantity is below a set threshold. You can tweak the code to work with any product category, price and discount percentage.

How It Works

The code loops through cart items looking for products assigned the t-shirt category
It counts the number of products in the cart
If there’s less than the threshold ( in this case 5 t shirts ) it calculates the price of adding more with discounts
It displays a message before the checkout with the discounted price of the product

Cart Messages

Messages are displayed based on quantity already in cart.

If the customer has a total quantity of 2, it displays a message “Add another for a discounted price of $18”.
If the customer has a total quantity of 3, it displays a message “Add another for a discounted price of 1$7”.
If the customer has a total quantity of 4, it displays a message “Add another for a discounted price of $16”.

Code

Here’s the code you can add to your child themes functions file or custom code snippets plugin.

add_action('woocommerce_before_cart', 'offer_discounted_tee_message');
function offer_discounted_tee_message() {

    if ( ! WC()->cart) return;

    $cart = WC()->cart->get_cart();
    $tshirt_category = 't-shirts'; // Update this to match your actual category slug
    $tshirt_price = 20; // Set your base T-shirt price
    $tshirt_count = 0;

    // Loop through cart items and count T-shirts
    foreach ($cart as $cart_item) {
        $product = wc_get_product($cart_item['product_id']);
        if ($product && has_term($tshirt_category, 'product_cat', $product->get_id())) {
            $tshirt_count += $cart_item['quantity'];
        }
    }

    if ($tshirt_count > 0 && $tshirt_count < 5) {
        // Discount structure
        $discounts = [
            2 => 0.05,
            3 => 0.10,
            4 => 0.15,
            5 => 0.20
        ];

        // Determine the discount for the next quantity
        $next_quantity = $tshirt_count + 1;
        $next_discount = isset($discounts[$next_quantity]) ? $discounts[$next_quantity] : 0.20;

        // Calculate the discounted price for adding one more
        $next_price = $tshirt_price * (1 - $next_discount);

        // Display the message on the cart page
        wc_print_notice("You can add another T-shirt for just <strong>£" . number_format($next_price, 2) . "</strong>!", 'notice');
    }
}