Shared boxes and ride-along items
Let different products share a box, and let small items ride inside a bigger product's box instead of shipping alone.
Updated October 13, 2026
By default each product packs on its own. The Box sharing tab on the Products page has two ways to combine products: shared boxes, where products that use the same box type fill it together, and ride-along rules, where a small item travels inside a bigger product’s box.
Both work inside one shipment, so the products must ship from the same location with the same carrier.
Before you start
Every product you want to use here needs a box of its own on the Box configuration tab: the box it ships in when it’s ordered alone. See Set up products.
Shared boxes
- Go to Products and open the Box sharing tab.
- In the Shop-wide card, tick Combine different products into shared boxes.
The setting saves at once and applies to every product, at checkout and on orders.
How products share
Products share a box only when both use the same box type and both have a Max qty per box above 1 on it. Each unit takes up its share of the box: one unit of a product with a limit of 2 fills half, one unit of a product with a limit of 4 fills a quarter. Parcello keeps adding units until the box is full.
| In the cart | Limits on the shared box | Boxes |
|---|---|---|
| 1 of product A, 1 of product B | 2 and 2 | 1 box (½ + ½) |
| 1 of product A, 2 of product B | 2 and 4 | 1 box (½ + ¼ + ¼) |
| 1 of product A, 1 of product B | 2 and 1 | 2 boxes |
A product with a limit of 1 fills a whole box, so it never shares. Products set up with different boxes never share either.
Two box columns of the same product never go in one box, even when they use the same box type. Two order lines of the same variant do share.
A shared box also stays within the box’s Max weight, when the box has one. See Box limits.
A piece limit for mixed boxes
Sharing by proportion doesn’t suit every box. When what limits a box is the number of pieces, whatever the mix, set Max pieces when products share this box on the box (on the Boxes page). A box holding two or more different products then holds at most that many pieces in total, and each product still stays within its own Max qty per box. The proportions above no longer apply to that box.
A box with Max pieces when products share this box set to 30, for long trim pieces: product A fits 30 per box, product B fits 60 per box.
| In the cart | Without the piece limit | With the piece limit of 30 |
|---|---|---|
| 20 of A, 10 of B | 1 box | 1 box (30 pieces) |
| 20 of A, 20 of B | 1 box (⅔ + ⅓) | 2 boxes (40 pieces is over 30) |
| 45 of B | 1 box | 1 box (one product only, so its own limit of 60 applies) |
A box holding only one product, or two order lines of the same variant, isn’t mixed: that product’s own Max qty per box applies. Riders don’t count toward the piece limit. The box’s limits show next to its name in the Ride-along rules card, for example “60 lbs max · Up to 30 pieces when mixed”.
With the setting on, different pack sizes of a carton family share mailers too, and products on automatic packing can share boxes with each other. See Limit items per box, alternative boxes and carton packs and Automatic packing by size.
Ride-along rules
Some small items ship in their own box when ordered alone but fit inside a bigger product’s box when both are on the order. A host is the product whose box has spare room. A rider is the product that fits in that room.
The Ride-along rules card groups the rules by box type, with the box name and size on each group.
Add hosts
- Click Add host, or Add host inside a box type’s group.
- In the Add hosts window, pick the Box type that has spare room.
- Under Host products, tick every product that leaves the same room in that box. Only products that ship in this box type on their own are listed. Search by product, variant or SKU, and use Select all shown to tick every match.
- In Room for add-ons, enter how many rider units fit in that box alongside the host’s own units (1 to 999).
- Click Save.
The hosts show under Hosts (open this box with room to spare) in that box type’s group. A product that ships in this box type more than once gets the room on its first box of that type; change it per box in the list afterwards. If a product you ticked doesn’t use the box type any more, Parcello skips it and names it in a banner, for example “Room for add-ons set on 4 products. Skipped 1 product that doesn’t use this box type: …”.
To change the room, edit the Room for add-ons field on the row. Remove takes the host off (the product keeps its box).
Add a rider
- Click Add rider, or Add rider inside a box type’s group.
- Search for the product in Rider product and pick it.
- Under Rides in these box types, tick every box type it can ride in. One rule is created per box type. Box types it already rides in are left as they are.
- In Units per box, enter how many of this product fit alongside the host.
- In Weight per unit, enter what each riding unit adds to the host box. It starts with the product’s Shopify weight.
- Optional: in Only on orders up to … host pieces, enter the largest number of host pieces an order can have for the rider to ride. See Ride only on small orders. Leave it blank to ride on any order.
- Click Save.
The rider shows under Riders (ride in this box when a host opens it). On its row you can change Up to … per box, the weight (lbs each) and Orders up to … host pieces (blank shows Any), or Remove the rule.
Copy riders to other box types
When a box type has riders, its group shows Copy riders to…. Pick the other box types and click Copy. Every rider of the first box type is added to them with the same count, weight and order limit. Products that already ride in a target box type are left alone. Hosts are not copied: set Room for add-ons on each box type’s host.
A group with riders and no host shows No host yet; one with hosts and no riders shows No riders yet. Riders have nowhere to go until the box type has a host.
How ride-along packs
Parcello packs every product first, then moves riders. A rider unit goes into a box only when:
- the box is the type the rule names,
- another product (a host) opened it, never the rider’s own box,
- the rider hasn’t reached its Up to count in that box,
- the box still has room for add-ons,
- the rider’s weight keeps the box within its Max weight, when the box has one, and
- the order is within the rider’s Orders up to … host pieces, when it’s set.
Whatever doesn’t fit stays in the rider’s own box. The host box’s weight goes up by the rider’s weight per unit, and its size doesn’t change.
A feeder whose box has room for 2, and a pack of nipples that rides up to 2 per feeder box:
| On the order | Boxes |
|---|---|
| 1 nipple pack | 1 small box (its own) |
| 1 feeder, 1 nipple pack | 1 feeder box with the pack inside |
| 1 feeder, 3 nipple packs | 1 feeder box with 2 packs, 1 small box with 1 pack |
| 2 feeders, 3 nipple packs | 2 feeder boxes, one with 2 packs and one with 1 |
Ride only on small orders
Sometimes a rider fits in a host box only while the order is small, for example a few spray cans that fit beside up to 10 trim pieces but not beside a full box. Set Orders up to … host pieces on the rider’s row (or Only on orders up to in the Add a rider window).
Parcello counts the pieces of every product that hosts that box type, meaning products with Room for add-ons on it. When the count is at or below the number, the rider rides as usual. Above it, the rider doesn’t ride in that box type: its units ship in their own box, or in another box type the rider has a rule for. The count is per shipment: products from another location or carrier aren’t counted. For a store with one location and one carrier, that’s the whole order.
Cans that ride in the trim box on orders up to 10 trim pieces:
| On the order | Boxes |
|---|---|
| 10 trim pieces, 4 cans | 1 trim box with the cans inside |
| 11 trim pieces, 4 cans | 1 trim box, and the cans in their own box |
Room in shared host boxes
When two products share a host box, its room is the smallest Room for add-ons set on any of them, and none if one of them has no room set. For a host on Alternative boxes, the room comes from the box the host actually ends up in, so set Room for add-ons on each size that has space.
Which products you can pick
Only products that already have their own box on the Box configuration tab can be picked, as a host or as a rider. The search finds products by product, variant or SKU and shows up to 60 matches. If your search hits a product with no box yet, a warning names it: assign its box on the Box configuration tab first, then pick it here.
Ride-along rules don’t show as box columns on the Box configuration tab, and editing a product’s boxes there keeps its rules and its room for add-ons.
Notes and limits
- Room and counts are numbers you declare. Parcello doesn’t check sizes.
- Products on automatic packing never host or ride along.
- Live rates at checkout pack the cart with the same rules.
- Orders already packed keep their boxes when you change a rule. Use Recalculate Packages on the order to repack it (only offered while no shipment on the order has a label).
Troubleshooting
“This product already rides along in that box.” The rule exists. Change its count or weight on its row instead.
The rider shipped in its own box. Check that the host and rider ship from the same location with the same carrier, that the host’s box type matches the rule, and that the host box has room left. Also check the rider’s Orders up to … host pieces and the box’s Max weight: a larger order, or a host box near its weight limit, sends the rider to its own box.
“Leave blank, or enter a whole number from 1 to 9999” Orders up to … host pieces must be blank or a whole number.
Two products didn’t share a box. Check that Combine different products into shared boxes is on and that both products have a Max qty per box above 1 on the same box. A box’s Max weight or Max pieces when products share this box can also close it before the next product fits.