The ladder we keep: nine half-kilo tiers on the line we follow most
The ladder holds nine rungs from 0.5 kg to 4.5 kg on the line we follow most closely, recorded at the 2026-09-25 review: 0.5 kg £6.80, 1.0 kg £8.20, 1.5 kg £9.90, 2.0 kg £11.60, 2.5 kg £13.30, 3.0 kg £15.00, 3.5 kg £16.70, 4.0 kg £18.40 and 4.5 kg £20.10 (Recorded, latest of 12 reviews since 2026-04-02).
Above 4.5 kg the rungs give way to a rate of £4.20 for each extra kilogram, and every figure here is a chargeable weight rather than a scale weight. The billing step is 0.5 kg, so a parcel is rounded up to the next half kilogram before it is priced.
1. Weigh the packed parcel. 2. Measure the box and divide length by width by height in centimetres by 6000. 3. Take the larger of the two figures. 4. Round it up to the next half kilogram and read the rung.
Note what the ladder does not cover. It prices one parcel on one service at one review date, and it says nothing about a split shipment, a second parcel or a service we have not reviewed, which is exactly why every rung on this site carries the date it was read from a screen.
Why 480 g and 520 g land on different rungs
A 480 g parcel rounds up to 0.5 kg and reads £6.80. A 520 g parcel rounds up to 1.0 kg and reads £8.20. Forty grams of difference moved the quote by £1.40, which is 3.5 pence per gram (Recorded, 2026-09-25 review).
The step is what does it. Rounding happens before pricing, so anything between 0.51 kg and 1.00 kg is billed as a full kilogram, and a parcel that sits just above a boundary pays for the whole next rung.
Small parcels are the worst case for this effect, because the first two rungs differ by £1.40 while the later rungs differ by £1.70. Pack a light parcel to land under the boundary rather than just over it, and check the packed weight rather than the listed weight.
Packaging is the lever with the shortest reach. Trimming 40 g from a 520 g parcel brings it under the 1.0 kg boundary and saves £1.40, while trimming the same 40 g from a 2.0 kg parcel changes nothing, because the rung is decided by the half kilogram rather than by the gram.
Weigh at home on a scale that reads to 0.05 kg and include the carton. A parcel measured without its box reads about 200 g light, which is enough to push a 0.9 kg basket past the 1.0 kg boundary once tape and filler are added, and on the recorded ladder that crossing costs £1.40 rather than being a rounding error.
Reading the ladder without assuming a straight line
The recorded rungs rise by £1.40 from 0.5 kg to 1.0 kg and then by £1.70 for each further half kilogram. Treating the ladder as a straight line at £3.40 per kilogram will therefore understate a light parcel and overstate a heavy one.
1. Find the rung above the chargeable weight. 2. Read the fee. 3. Find the next rung and note the gap. 4. Compare the gap with the cost of removing weight from the parcel.
The comparison is the useful part. Where 400 g of packaging would move a parcel down one rung, the saving is £1.70, and that is the number to weigh against the protection the packaging provides.
Compare two parcels rather than two prices. A 2.4 kg parcel and a 2.6 kg parcel sit £1.70 apart on the ladder, and the cheaper one is not better value; it is simply lighter, which only matters when the goods inside the two parcels are genuinely equivalent in the first place.
The four jump points that surprise people
Jump one is the boundary at 1.0 kg, worth £1.40, which catches parcels of 480 g to 520 g and anything else that ignores the packing material when it is weighed at home.
Jump two is the 4.5 kg boundary, where fixed rungs give way to £4.20 per extra kilogram. A 5.0 kg parcel is priced from the 4.5 kg rung, so the fifth kilogram costs more than the fourth did.
The 200 cm side limit is the third of them, above which the parcel has to be split whatever it weighs. Jump four is the 50 kg mark, where most lines require a split regardless of dimensions. Both limits come from the same tool logic we use for chargeable weight.
The same jump points decide how a split behaves. Two parcels sitting below 4.5 kg each pay two opening rungs, while one parcel above the boundary pays a single opening rung plus £4.20 for every kilogram past it, and the two totals can land within pennies of each other.
Measure the box after packing rather than the item before it. Adding three centimetres to one side of a 40 by 35 by 30 cm box creates 3,000 cubic centimetres, which is half a kilogram of volumetric weight and enough to cross a rung without any goods being added at all.
Outliers: the 6.5 kg parcel that billed at 7.0 kg
One recorded parcel weighed 6.5 kg on the scale and billed at 7.0 kg. The box measured 40 by 35 by 30 cm, which is 42,000 cubic centimetres, and at the 6000 divisor that is exactly 7.0 kg of volumetric weight (Recorded, 24 parcels, window 2026-08-01 to 2026-09-30).
The scale weight never mattered. Where the volumetric figure is larger, the volumetric figure is the chargeable weight, and 500 g of the bill came from air inside a box rather than from anything inside the parcel.
Two explanations are worth ruling out before blaming the box: a divisor of 5000 rather than 6000 would have produced 8.4 kg, and a tape measure reading that adds 2 cm to each side would have produced 8.0 kg. Both errors are more common than a genuine line surcharge.
Check the divisor before questioning the service. A 5000 divisor turns the same 42,000 cubic centimetre box into 8.4 kg rather than 7.0 kg, and a parcel billed that way is not being overcharged; it is being priced by a different rule that the quote should name.
The 200 cm side limit catches long items before weight does. A rolled tube or a pair of skis crosses that limit while weighing under 3.0 kg, and above it the parcel has to be split whatever it weighs, which turns one rung into two opening rungs and two handling fees on the same goods.
Work the outlier check in order before blaming the service: the divisor first, because 5000 turns the same box into 8.4 kg rather than 7.0 kg; the tape measure second, because 2 cm on each side adds a kilogram; and a surcharge last, because it is the only one of the three that would appear as a separate line.
Turning the ladder into a packing decision
Decide before the parcel is packed, not after. A rung is chosen by the chargeable weight of the packed box, so the last 400 g of packaging is often the most expensive material in the whole order.
1. Weigh the goods and the box separately. 2. Price the packed parcel on the ladder. 3. Remove one layer and price it again. 4. Keep the lighter packing where the protection still holds.
Keep the ladder reviewed rather than remembered. The figures here carry a review date of 2026-09-25 and 12 reviews sit behind them since 2026-04-02, which is the reason every rung on this site comes with a date attached.
Keep the last three bills beside the ladder. Three orders that billed at 0.5 kg, 1.0 kg and 4.5 kg are enough to confirm that the rungs being read are the rungs being applied, and that comparison costs a minute against a query that costs a week.
The data point behind this note
On the recorded ladder a 480 g parcel bills at the 0.5 kg rung of £6.80 and a 520 g parcel at the 1.0 kg rung of £8.20, so 40 g moved the quote by £1.40 (Recorded, 2026-09-25 review).
Rates last checked 2026-10-02. Where a figure is community-reported we say so; where we could not verify it, we write Not verified instead of estimating.