Description:
In this scenario, you’re facing an issue where the product add-ons are visible, but you are unable to add them to the product box. Please refer to the screenshot.

This is likely because the box isn’t configured as “purchasable” in WooCommerce. When a product box isn’t purchasable, no add-ons can be added to the cart.
Here’s a step-by-step explanation of what’s happening and how you can fix it:
Explanation:
1. Check if there is an ‘Add to Cart’ button:
- First, check if the “Add to Cart” button is visible on the product page. If this button is missing, it means that WooCommerce has flagged the product as non-purchasable. WooCommerce will only display the “Add to Cart” button when the product is properly configured to be sold.
2. Check the price of the product box:
- A WooCommerce product must have a price to be purchasable. If the box doesn’t have a price set (either a regular price or a sale price), the system will mark it as unpurchasable, preventing customers from adding it to their cart.
What can you do to fix this?
Scenario 1: The product box needs a price
- To resolve this issue, make sure to set a regular price for the product box. This regular price tells WooCommerce that the box is a product that can be purchased.
Scenario 2: You only want to charge for the add-ons, not the box
- If you want the box to be free and only charge for the add-ons, you can set the box’s regular price to $0. Then, you need to configure the pricing type for the box to “Only add-on products price”. This way, the system understands that the box itself is free, but the add-ons have a price.
Example Scenarios:
Example 1: Regular product box with a price Let’s say you have a “Gift Box” that costs $50. In WooCommerce, you need to set the price of the gift box to $50. Now, if a customer wants to add any extras (add-ons) like a ribbon or custom message, those can be added for an additional charge, say $5 for the ribbon.
- Box price: $50
- Add-on (Ribbon): $5
- Total: $55
In this case, because the box has a price, it’s purchasable, and the customer can add it to the cart along with the add-ons.
Example 2: Free box with add-ons priced Imagine you want to offer a free “Sample Box” but charge for the items inside (add-ons). You would set the regular price of the box to $0 and configure the pricing type to “Only add-on products price.” Now, if a customer selects add-ons like a chocolate bar for $2 and a pen for $3, the total will be based solely on the add-ons.
- Box price: $0
- Add-on (Chocolate): $2
- Add-on (Pen): $3
- Total: $5
In this setup, the box is free, and the add-ons are what create the final price.
Key Takeaway:
- For a product box to be purchasable in WooCommerce, it must either have a regular price set or have the pricing type configured to charge for add-ons only. Setting the box price to $0 while charging for add-ons can give you flexibility in your pricing strategy.
By following these steps, you should be able to ensure that your customers can add both the product box and the add-ons to their cart seamlessly.