Key takeaways
- Cost per trip = (unit price + freight − residual) ÷ effective trips. Most buyers have one of those four inputs.
- Used 2A runs about $1.98 a trip against $4.06 for new; the cheapest option on the table is the worst of all at $4.75.
- Effective trips is a divisor, which is why it has the largest leverage and is the input nobody measures.
- Residual value is negative if your supplier will not buy the container back — disposal costs money.
Almost every packaging purchase in North America is evaluated on unit price, because unit price is the number on the invoice and the number in the procurement system. It is also, in reusable packaging, close to meaningless on its own.
The formula
Cost per trip = (unit price + freight per unit − residual value) ÷ effective trips achieved.
Four inputs. Most buyers have one.
Unit price
The easy one, and the one everybody optimises. It is typically fifty to seventy per cent of the answer and it gets ninety-five per cent of the attention.
Freight per unit
Enormous for bulky low-value goods. Flattening changes this by a factor of twenty or more. Backhaul availability on your lane changes it again. A box that is a dollar cheaper and ships assembled is not cheaper.
Residual value
What the container is worth when you have finished with it. If your supplier buys boxes back, this is two to three dollars on a five-wall gaylord. If they do not, it is a negative number — because disposal costs money.
Effective trips
How many journeys you actually get, after damage and losses. This is the input nobody measures and the one with the largest leverage, because it is a divisor.
| Option | Landed unit price | Effective trips | Residual | Cost per trip |
|---|---|---|---|---|
| New 5-wall | $22.65 | 5.8 | −$0.90 | $4.06 |
| Used 2A 5-wall | $11.40 | 4.7 | +$2.10 | $1.98 |
| Used 3A 5-wall | $9.15 | 3.2 | +$1.30 | $2.45 |
| Used 4A, reconditioned | $7.60 | 2.1 | +$0.60 | $3.33 |
| Used 4A, as-is | $5.90 | 1.2 | +$0.20 | $4.75 |
On unit price, the last row wins by a mile. On cost per trip it is the worst option on the table — worse than buying new. That inversion is the entire point.
When the cheap box genuinely wins
When effective trips is one whatever you buy. One-way outbound shipments, processes that destroy containers on discharge, material that goes to a customer and never returns. In those cases durability is a donation and the cheapest surviving box is correct.
Which is why most well-run operations buy two grades: a better one for the loop, a cheaper one for the one-way flow. Very few do, because procurement systems dislike two part numbers for the same thing.
Getting the trips number
Mark fifty boxes with a paint pen. Record weekly how many are still in service. Twelve weeks. Five minutes a week. It is the only way to get this figure, no supplier can give it to you, and nearly everyone who does it finds the real number is well below the assumption.
The line that usually gets missed
Residual value. Ask any supplier whether they will buy the containers back at end of life. If the answer is no, that line is not zero — it is negative by whatever your disposal costs, which for most sites is somewhere between forty cents and a dollar per box once compactor pulls are apportioned.
Questions