KubovaWhen You Can Avoid a Second Container — and When You Genuinely Can’t
By Kubova Team
A load that spills just past one container is one of the most expensive things in shipping — you pay for a whole second box to carry almost nothing. The good news: a marginal spill is often a planning choice, not a hard limit. Here’s how empty that second container really is, the levers that pull a load back under the line, and when it genuinely can’t be done.
The second container is usually empty
We took loads sized to spill just past a single 40 HC and measured how full the second container ended up. It was never close to full:
Single-SKU 60×40×40 cm loads spilling just past a one-container fit, Kubova engine, measured 2026-06-08.
Four levers that pull a load back under the line
A good engine already returns the best geometry for the inputs you gave it — so you don’t consolidate by re-running, you consolidate by changing the inputs:
- Allow more rotation. Every “this way up” rule you can safely drop gives the packer orientations that close gaps.
- Change the pallet base. A base that tiles the container floor in whole rows can recover a bay — the same carton can swing 50%+ in boxes-per-pallet by base (see boxes per pallet).
- Swap container type. A High Cube’s extra height adds a layer; sometimes a 40 DC + 20 DC beats two 40s. Compare them.
- Mix more SKUs. Adding another product’s small cartons can fill the gaps — mixed loads reach higher fill than single-SKU ones (see mixed-SKU loading).
Before you book a second container — a 5-step check
- How full is the second container? If it’s under ~25%, this is likely recoverable.
- Which constraint stopped you — volume or weight? (Weight isn’t fixable by re-packing.)
- Can any cartons rotate that currently can’t?
- Would a different pallet base or container type fit one more bay?
- Is there other cargo on the same lane to consolidate with?
See if your load fits in one
Try rotation, pallet and container options and watch the container count. Free to start.
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Frequently asked questions
How can I avoid shipping a second container?
When a load just spills over, the second container is usually mostly air — in our tests it averaged only ~17% full. That waste is often recoverable by changing inputs you control: allow rotation on more cartons, pick a pallet base that tiles the container better, swap to a taller container, mix more SKUs to fill gaps, or trim a marginal item. You can’t squeeze geometry that’s already optimal, but a marginal spill frequently isn’t a true overflow — it’s a planning choice.
When is a second container genuinely unavoidable?
When you’re actually out of room or weight: the cargo volume truly exceeds one container after an optimal pack, you’ve hit the payload limit, or items are oversized and can’t be reoriented. In those cases a second container isn’t waste — it’s necessary.
How empty is the second container when a load spills?
For loads that spill just past a one-container fit, our engine runs put the second container at roughly 10–25% full (about 17% on average). In other words, more than 80% of that second container is empty space you’re paying to ship.
Does re-running the calculator find a better answer?
Not by itself — a good engine already returns the optimal geometry for the inputs you gave it. The gains come from changing the inputs: rotation rules, pallet choice, container type, or which SKUs travel together. That’s where a marginal load gets consolidated.
Who: Written and reviewed by the Kubova team, who build and operate the packing engine described here.
How: Drafted with AI assistance for research and structure; the technical claims, examples and product details are owned and verified by the team.
Why: To help logistics and engineering teams decide whether to let an AI agent plan their loads — not to chase a keyword. Published 2026-06-08.