Match the allocation driver to the charging driver
Every surcharge was calculated from something. Fuel was calculated from base carriage. A re-weigh was calculated from one parcel’s measured weight. A remote-area fee was calculated from one destination. Allocate each charge using the same driver the carrier used, and the resulting cost per order is defensible. Use anything else and you are choosing to move money between orders.
| Charge type | Allocate to | Basis |
|---|---|---|
| Base carriage | The shipment | Direct, one to one |
| Fuel surcharge | The same shipment | Pro rata to that shipment’s carriage |
| Re-weigh / dimensional | The specific parcel | Direct; never averaged |
| Oversize / non-conveyable | The specific parcel | Direct; drives SKU-level decisions |
| Remote area / zone | The specific shipment | Direct; informs shipping-rate policy |
| Account and collection fees | All shipments in the period | Spread, shown as its own line |
What averaging actually costs you
Take an illustrative month: 1,000 parcels, average base carriage £4.20. Sixty of them are oversize and carry £6.50 each in extra charges, £390 in total.
- Averaged. £390 spread over 1,000 orders adds 39p to every parcel. The 940 ordinary parcels each look 39p worse than they are, and each oversize parcel looks £6.11 better.
- Allocated. The 60 oversize parcels each carry £6.50. The bulky SKU now shows its real contribution, which is the number you need when deciding whether to keep listing it, reprice it, or change the packaging.
The averaged version is not merely less precise. It points the decision in the wrong direction, because it makes the problem SKU look normal and the healthy ones look marginal.
Where the allocated cost has to land
Allocation is only useful if it reaches the margin figure people act on. In MaxInvent, allocated charges attach to the orders responsible, and order and marketplace profit reporting reads the invoiced cost rather than the rate quoted at booking. Packaging and label costs can be set as per-order and per-parcel defaults, so the small recurring amounts are inside the number rather than forgotten.
Two adjacent decisions are worth separating from this one. Choosing a service at booking time is courier selection, and getting the invoice matched in the first place is reconciliation. Allocation sits between them.
How to check your own allocation is honest
- Pick the ten highest-value surcharge lines from one invoice and confirm each landed on a specific order.
- Take your bulkiest SKU and compare its reported margin before and after allocation. If nothing moved, the allocation is not reaching margin.
- Confirm account-level fees appear as their own line rather than inside carriage, so a volume drop is visible as a per-parcel rise.
- Check that the unallocated remainder is small and shrinking, and that someone owns it.