How Parcello packs an order
The order in which Parcello applies your packing rules, what the order page shows, and when to use Recalculate Packages.
Updated October 26, 2026
Parcello turns an order’s items into shipments and boxes using the rules you set on the Products and Boxes pages. This page explains when packing happens, the order the rules apply in, and how to repack an order after you change a rule.
When packing happens
- When an order arrives. New orders come in from Shopify on their own, and Sync Orders on the Orders page brings in older ones. Each order is packed as it comes in.
- When you first open an order with no shipments. An order that arrived before you set up a location, a carrier or your boxes gets its shipments the first time you open it.
- When you click Recalculate Packages. See below.
Changing a rule doesn’t repack orders that are already packed.
Which items Parcello packs
Parcello leaves out:
- items whose product ships from a location marked Dropship / 3PL Location,
- items Shopify assigns to an outside fulfillment service,
- orders Shopify records as local pickup, local delivery or an in-store sale (the order page says the order doesn’t need a shipping label and offers Create shipment anyway).
An item whose product has no box and no automatic size still lands in a shipment, but without a box. It shows as Not assigned on the order page until you add a box for it.
The order the rules apply in
1. Shipments by location and carrier
Items are grouped by where they ship from and which carrier ships them. Each group becomes one shipment. The carrier comes from the product’s own carrier, then the shipping method the customer picked at checkout, then your store default, then the first carrier you connected. See How Parcello picks the carrier and service.
On the Freight plan with Estes or FedEx Freight connected, products set to a freight carrier, and products whose box is too large or heavy for parcel carriers, go to a freight shipment. With Consolidate parcel items onto a freight shipment on, parcel items from the same location ride the freight shipment too. See Freight with Estes and Freight with FedEx Freight.
Everything below happens inside one shipment. Products in different shipments never share a box.
2. Each product’s own boxes
Every product on box rules packs into its box columns:
- Unit split across boxes: each unit gets one of each box. See Ship one product in several boxes.
- Max qty per box: each box holds up to that many units before the next one opens.
- Max weight (set on the box, on the Boxes page): the box also closes before its weight, box and contents, would go over the limit. A unit heavier than the limit on its own ships alone in that box. See Box limits.
Box limits apply to every step below too.
3. Shared boxes
With Combine different products into shared boxes on, products that use the same box type with a Max qty per box above 1 fill shared boxes together. When the box has Max pieces when products share this box, a box holding different products takes at most that many pieces, each product within its own Max qty per box. See Shared boxes and ride-along items.
4. Smaller sizes for part-filled boxes
For products on Alternative boxes, the box with the largest Max qty per box packs first, and a box that isn’t full moves down to the smallest size that holds it, within that size’s Max weight. A shared box moves down only when every product in it has that smaller size. See Alternative boxes.
5. Carton packs
Products on Alternative boxes that use Cartons per unit above 1 or a box marked Only when nothing else fits (and products sharing their box types) are packed by cartons: boxes fill largest first, each box moves down to the smallest size that holds its cartons, and cartons are moved between boxes to avoid the marked box. These boxes come after the boxes from steps 2 to 4. See Carton packs.
6. Ride-along items
Riders move into boxes their hosts opened, as far as each host box’s room and Max weight allow. A rider with Orders up to … host pieces set rides only when the shipment has at most that many pieces of the products that host the box. Riders that don’t fit stay in their own box, and a rider box left empty is dropped.
7. Automatic packing (Operations plan)
Products on automatic packing are packed by size from your box library, after everything else. They never share a box with products on box rules. See Automatic packing by size.
What the order page shows
The Package Assignments card lists every box of the order across the top (Box #1, Box #2 and so on, with the box name under each, or Custom for a box with your own dimensions). Within a shipment, boxes are numbered in the order above. Line items run down the side, each with how many are left to ship as Shopify counts them (“2 to ship”, “1 of 2 left to ship” or “All 2 fulfilled”), how many boxes it’s assigned to, and the weight of one unit.
Each cell is the number of units of that line item in that box. A product split across three boxes reads 1 in all three for one unit. Changes save as you make them.
For a product whose every unit goes in one box (one box type, Alternative boxes or automatic packing), Parcello adds up the line’s cells and compares them with the units ordered, while nothing on the line is fulfilled yet. When they differ, the row says so in orange: “1 of 2 in a box” when a unit is in no box, or “6 in boxes, 3 ordered” when units are counted more than once. Fix the cells before you create the label: the label’s weight and declared value, and the packing slip, come from them. Products split over several boxes per unit aren’t checked, because every box of the set holds the same unit.
Each shipment card below lists its boxes in Assigned Packages, with their weights and a Move to different shipment choice. A box heavier than its box type’s Max weight shows “Over this box’s N lbs limit” under its total weight. A box with a label is locked; the others stay editable. See Boxes and shipments on the order.
Recalculate Packages
Recalculate Packages throws away the order’s shipments and boxes and packs it again from your current rules. Use it after you change a product’s boxes, a sharing rule or a setting, or to undo changes you made by hand.
- Open the order.
- Click Recalculate Packages at the top of the page.
- Read the warning: “This will reset all package assignments and shipments to defaults based on variant configurations. Any manual adjustments will be lost.”
- Click Recalculate.
Recalculate Packages is only offered while the order has shipments and none of them has a label. A voided label counts too: once a shipment has had a label, even a voided one, the button is gone. In that case, change the unlabeled boxes by hand.
Checkout uses the same rules
Live rates at checkout (Advanced plan) pack the cart with the same rules, in the same order, before asking carriers for prices. The boxes on the quote are the boxes the order starts with. If the cart has an item with no box and no automatic size, checkout can’t price it and Shopify shows your backup rates. See How checkout prices a cart and Why checkout shows backup rates.
Notes and limits
- Box rules are counts you declare, plus the weight limit you set on a box. Only automatic packing looks at sizes.
- Orders keep their boxes when you change a rule. Recalculate the ones you want to repack.
- When an order changes in Shopify, Parcello takes units the order no longer has out of boxes that don’t have a label yet. See When an order changes in Shopify.
Troubleshooting
“Cannot recalculate: some shipments already have labels created” A shipment on the order got a label (or a voided one) after the page loaded. Edit the unlabeled boxes by hand instead.
“Cannot recalculate: no shipping address available for this order” The order has no shipping address in Shopify. Add one in Shopify, then try again.
A row says “1 of 2 in a box” in orange. One unit of that item is in no box, for example after its box was deleted. Set the right number in a box’s cell, or add a box with Add Package and assign it.
A row says “6 in boxes, 3 ordered” in orange. The item is counted in more boxes than were ordered, for example after an order edit removed units but their boxes stayed. Lower the cells, or delete the extra box with its trash icon.
An item shows Not assigned. Its product has no box (or no automatic size) for that location, or the order was packed before you set it up. Add the box on the Products page, then use Recalculate Packages, or add a box with Add Package and assign the item.
The order page has no shipments. The order may be pickup or local delivery, every item may ship from a dropship location, or no location was set up when it arrived. Set up a location and open the order again.