What Happens to Your Parcel at a Sorting Hub

Between the rider picking up your parcel and the buyer receiving it, the parcel is weighed and measured at least once by a machine that does not know what you declared. Knowing what that machine does, where in the journey it does it, and what happens to its reading explains almost every weight discrepancy you will ever see.

Where the check happens

At pickup: usually nothing. Riders scan the label and take the parcel. Some carriers give riders a handheld scale for spot checks, but the rider’s reading is not the billing reading.

At the origin hub: the first real check. Within hours of pickup the parcel reaches the courier’s local hub or sorting centre. Here it goes across a scale, and at larger hubs through a dimensioning tunnel: a conveyor with a weighing plate and overhead sensors that measure length, width and height in a fraction of a second as the parcel passes. The reading is stored against the AWB.

At transit hubs: sometimes again. Large mother hubs may re-measure. If two readings exist, carriers generally bill on the origin hub’s.

At the destination: rarely. The delivery hub sorts by pincode, not weight.

So the reading that matters is taken within a day of pickup, by an automated system at the first hub, on the parcel exactly as your packer sealed it.

What the machine measures

Dimensioning scanners measure the smallest box the parcel fits in, as it lies on the belt. That has consequences.

• A parcel with a bulging side, a loose flap or a strap sticking out measures larger than the box’s nominal size.
• A soft parcel (a poly mailer with a soft product) can measure taller than it “is” if it sits puffed up on the belt.
• A parcel placed on its side measures the same volume, so orientation does not matter, but a parcel resting on another parcel’s edge can.

The scale is accurate to 10 g or better. The dimensions are accurate to about 1 cm. That is enough precision to move a parcel across a slab edge.

What happens to the reading

The courier’s billing system compares the chargeable weight from its measurement with the chargeable weight from the booking. Where the measured figure lands in a higher slab, the courier charges the difference to the platform in its periodic billing file. The platform raises a weight discrepancy against your shipment, with both sets of numbers and the courier’s evidence where supplied (a scanner record or a photo), and gives you seven days to accept or dispute.

Timing: the reading exists within a day; the billing file arrives days to a couple of weeks later. That is why a discrepancy can appear after the parcel was delivered.

Why readings differ from declarations

In descending order of frequency, from what ops teams see:

1. The declaration was bare product weight, not the packed parcel. The hub weighs the packed parcel.
2. Dimensions were blank or stale. The hub measures the box that was used.
3. The box was larger than the SKU record, because the packer substituted.
4. A soft parcel measured puffy on the belt, or a flap was loose.
5. A scanner error, usually two parcels touching on the belt. Rare, but it happens, and it is the case a dispute exists for.

The first three are the seller’s data. The fourth is packaging technique. Only the fifth is the courier’s mistake.

Working with the hub, not against it

Seal tight and square. A parcel that measures the same as its box is one whose flaps are taped down and whose contents do not push the sides out. Fill the box or size it down; do not ship a half-full box that bows.

Keep straps and tags inside the footprint. Anything protruding adds centimetres.

Declare what the hub will see. Packed weight, outer dimensions, to the centimetre.

Photograph before handover if the parcel is near a slab edge. Thirty seconds at the packing bench: parcel on the scale, tape across one dimension, AWB visible. If the hub reading crosses the edge and yours does not, that photo is the dispute.

Watch by courier. Every discrepancy names the courier. If one courier’s hub produces a discrepancy rate three times the others on comparable parcels, its scanner or its process is the outlier, and the platform’s ops team takes that up with the carrier.

What the courier’s evidence looks like

When a discrepancy is raised, the courier’s side of it is one of: a dimensioning scanner record (weight and three dimensions with a timestamp), a hub photo of the parcel on a scale with the reading visible, or, from smaller hubs, just the figures. On Courier Uncle the record shows whatever the courier supplied, labelled as such, alongside your declaration. If the courier supplied nothing but figures and your evidence is a dated scale photo with the AWB in frame, the dispute usually goes your way.

Frequently asked questions

Does every parcel really get measured?

At hubs with dimensioning tunnels, yes, every parcel on the belt. At smaller hubs, weighing is universal and dimensioning may be sampled. Assume every parcel is measured.

Can I see the hub’s reading?

When a discrepancy is raised, yes: the measured weight and dimensions are on the record, with the courier’s evidence where supplied. When there is no discrepancy, the reading is not surfaced, because there is nothing to act on.

How accurate are the scanners?

Weight to 10 g, dimensions to about 1 cm. Discrepancies of a few grams or a centimetre almost never cross a slab edge; the ones that do reflect a real difference between the declaration and the parcel.

What if two parcels were scanned together?

That is the classic scanner error, and it produces a reading far larger than any parcel you sent. Dispute it with your scale photo; these are resolved quickly because the numbers are obviously wrong.

Why did the reading take two weeks to reach me?

The hub reading is immediate; the courier’s billing file is periodic. The seven-day dispute window starts when the notice reaches you on the platform, not when the parcel was scanned.

Does a soft mailer measure bigger than it is?

It can, if the contents leave it puffy. Press the air out and seal flat. A mailer that lies flat on the belt measures its true dimensions.

Ship smarter with Courier Uncle

See both sides of every weight reading, with the courier’s evidence and seven days to respond. Ship with the hub’s numbers visible.