Whether to take a container or join a groupage box is the question we are asked most, and the answer is not the size of the shipment. It is three numbers: cubic metres, density, and how much slack the deadline has. Work those out and the choice usually makes itself.
Not the shipment size on its own. Cubic metres, cargo density, and how much slack the deadline has. Send those three and the answer is arithmetic — the rest of this page is why.
| Number | How to get it | What it decides |
|---|---|---|
| Cubic metres | L × W × H in metres × pieces, measured over the outer packaging | Whether you are below or above the 10–13 CBM break-even |
| Density | Gross tonnes ÷ cubic metres | Whether a 20GP carries your tonnage; above 0.88 t/CBM a 40ft is wasted |
| Slack | Days between booking and the date the cargo must be on shelf in Iran | Under 40 days, groupage waiting time becomes a real risk |
The common assumption is that you need to fill a 40ft before FCL makes sense. Not so. A 20GP holds roughly 33 CBM, but on the Iran lane the 25.5-tonne weight ceiling usually stops many commodities well before the volume is used.
In practice: below roughly 10–13 CBM groupage tends to cost less in total; above it, FCL wins on unit cost. FCL is a fixed cost spread over the boxes you ship — the more cubic metres, the thinner it spreads. LCL is priced per cubic metre with no spreading effect, so it never gets cheaper the more you send.
| Volume | Default | Why |
|---|---|---|
| 1–5 CBM | LCL | FCL fixed costs have nothing to spread over |
| 5–10 CBM | Mostly LCL | Approaching the break-even; worth pricing both |
| 10–13 CBM | Either — price both | Gap is small; the deadline decides |
| 13–25 CBM | FCL, 20GP | Unit cost already under LCL, and no waiting for consolidation |
| Over 25 CBM | FCL, 40HQ or multiple 20GP | Check density first — heavy cargo may need two 20GP |
The trap on this lane: a 40ft does not carry more tonnes than a 20GP. The rail ceiling is 25.5 tonnes of cargo per container, identical for both sizes.
So heavy cargo in a 40ft means paying freight on air. The test is simple:
| Density (t/CBM) | Cargo | Box |
|---|---|---|
| Under 0.38 | Furniture, textiles, plastics, packaging | 40HQ |
| 0.38 – 0.88 | Small appliances, hardware, general merchandise | Usually 40HQ |
| Above 0.88 | Tiles, steel coils, fertiliser, castings | 20GP |
LCL is priced differently: by chargeable cubic metre at 1 CBM = 500 kg, minimum 1 CBM. One cubic metre of cargo weighing three tonnes is charged as six cubic metres. Heavy cargo in groupage gets amplified — worth knowing before you ask for the rate, not after.
Station to station, both modes run 25–35 days; door to door, 28–40. On paper identical. The difference is how much of that time you control.
| Dimension | FCL | LCL |
|---|---|---|
| Where the time goes | Waiting for a departure, then transit, then arrival | Waiting for co-loaders, waiting for a departure, transit, deconsolidation |
| Biggest uncertainty | Whether you get space at all | When the other shippers' cargo arrives |
| Departure rhythm | Stuff as soon as space is confirmed | Waits until the box is full enough |
| Damage exposure | Your box, fewer handlings | Multiple handlings; packing has to be better |
| Accepted cargo | Broader, including some special cargo | No DG, no lithium batteries, no liquids or powders |
Either way, build 5–7 days of buffer into a hard deadline. With LCL, add the consolidation wait on top of that.
| Step | Ask | Yes → | No → |
|---|---|---|---|
| 1 | Is the volume above 13 CBM? | Go to step 2 | LCL, unless the deadline is tight |
| 2 | Is density above 0.88 t/CBM? | 20GP — weight binds first | 40HQ — buy the volume |
| 3 | Can this shipment wait for consolidation? | LCL is worth the saving | FCL, keep control of the date |
If you land in the 10–13 CBM band, the practical move is to price both. We quote FCL and LCL side by side with destination charges included, so the comparison is on total cost rather than a headline rate.
Usually from about 10–13 CBM upward, but it depends on commodity and the current rate. Inside that band the gap is small enough that pricing both is the only honest answer.
By chargeable cubic metre at 1 CBM = 500 kg, minimum 1 CBM. One cubic metre weighing three tonnes is charged as six. Give us volume and gross weight and we will state the chargeable figure.
25.5 tonnes of cargo net weight, the same for 20ft and 40ft, excluding tare. It is a railway limit with no waiver route.
More volume, same 25.5-tonne ceiling. For light cargo a 40HQ is right; for heavy cargo a 40ft wastes volume and freight.
On paper not slower: 25–35 days station to station either way. In practice LCL adds a consolidation wait that FCL does not have, so on a hard deadline the difference can be a week or more.
No. A groupage container mixes several shippers' cargo, so DG, lithium batteries, liquids and powders are excluded. Those go FCL with a separate declaration.
The most awkward and also the easiest place to be: get both priced, including destination charges, and compare totals. Sometimes FCL costs marginally more and arrives a week sooner — whether that is worth it is your call, not ours.
Yes, but decide before booking. Changing after stuffing means re-declaring, which costs money. Tell us the volume you expect each time you enquire and we will flag when you are near the band.
Yes, but freight is per container and the empty space is not refunded. Run the numbers: the cost of the air against the LCL rate for what you actually have.
The Xi'an–Tehran rail LCL service is the one regular Iran-bound groupage line in operation. Exact departure arrangements for a given week are confirmed at booking.
Origin and email are enough - the rest can follow later. We reply in writing so you keep everything on record.