Texon Multi-Box Shipping

A custom WooCommerce plugin that allows configuring multiple shipping boxes per product for accurate carrier rate calculations.

The Problem

Heavy or bulky products like RedShopTowels-A (149 lbs) get sent to FedEx as a single package, resulting in inflated shipping rates due to overweight surcharges. In reality, these products ship in multiple smaller boxes. For example, a product quoting $220 as a single package actually costs ~$78 when split into the 4 boxes we actually use.

How It Works

1. Configure boxes per product — In the WooCommerce product editor, a "Multi-Box Shipping" tab lets you define multiple boxes with individual weight and dimensions.
2. Automatic package splitting — When a customer adds the product to their cart, the plugin splits it into separate packages behind the scenes before the carrier API (FedEx, USPS, etc.) calculates rates.
3. Combined rate display — After rates are calculated per box, the plugin merges them back into a single shipping line so the customer sees one clean total — not separate lines per box.

Features

• Configure multiple boxes per product (label, weight, L/W/H dimensions)
• Supports both simple and variable products
• Per-variation box overrides (variations inherit parent boxes unless they have their own)
• Automatic proportional value allocation across boxes (by weight)
• Single combined shipping line in cart/checkout (no confusing per-box selectors)
• Works with any carrier plugin (FedEx, USPS, UPS, etc.)
• WooCommerce HPOS compatible

Installation

1. Upload the texon-multi-box-shipping folder to wp-content/plugins/
2. Activate the plugin in WordPress admin
3. Edit a product and go to the "Multi-Box Shipping" tab to configure boxes

Configuration

Simple Products

1. Edit the product in WooCommerce
2. Click the "Multi-Box Shipping" tab in the Product Data panel
3. Click "+ Add Box" for each box the product ships in
4. Enter the weight and dimensions for each box
5. Save the product

Variable Products

• Parent-level boxes apply to all variations by default
• To override for a specific variation, expand the variation and add boxes in the "Multi-Box Shipping" section
• Variations with their own boxes will use those instead of the parent's

Technical Details

• Box configurations are stored in _texon_shipping_boxes post meta
• Package splitting hooks into woocommerce_cart_shipping_packages at priority 5 (before carrier plugins)
• Rate merging hooks into woocommerce_shipping_packages at priority 10 (after rate calculation)
• Product value is split proportionally across boxes by weight for accurate declared values

Version History

1.1.0

• Added per-variation box configuration support
• Variations can override parent product boxes or inherit them

1.0.0

• Initial release
• Multi-box configuration for simple and variable products
• Package splitting and rate merging
• Single combined shipping line display