What “rate shopping” actually means
Rate shopping is when the inventory or dispatch platform queries the live rate API of every connected courier at the moment a label needs to be generated, gets a real quote based on the actual weight, dimensions and destination of the parcel plus your negotiated contract rates, and either auto-selects the cheapest compliant option or ranks the options for the dispatcher to choose from.
It's the opposite of what most small UK sellers do, which is: decide on “my default Royal Mail service” and use it for everything unless the parcel is obviously too big. That default rule is usually leaving money on the table — typically 8-15% of total courier spend once volume is above ~200 parcels a day.
The three quality levels of “rate shopping” in software
- Static rate cards.The platform has stored rate cards from each courier. It “rate shops” by looking up the rates in its database. Fine for rough picks, but the data goes stale the moment a courier does a price adjustment — which is often multiple times a year.
- Live API rate shopping with platform rates. The platform queries each courier's live rate endpoint but uses the platform's own negotiated contract — which is then marked up to you. You get live accuracy, but you pay the platform's margin on every label.
- Live API rate shopping with your own contracts. The platform connects to each courier using your account credentials and your contract rates. Live accuracy, no mark-up. This is the model that scales past ~1,000 parcels/month economically.
The UK couriers to connect
| Courier | Sweet spot | Also good for |
|---|---|---|
| Royal Mail | Small parcel tracked, letters, international | B2C under 2kg |
| DPD | Next-day tracked 2-30kg, B2B | Fragile items (predictable handling) |
| Evri | Cheap small parcel, drop-off focused | Price-sensitive B2C under 2kg |
| Parcelforce | Heavy parcels 10kg+, palletised | B2B business-address deliveries |
| Amazon Shipping | Competitive cross-London/UK rates | High-volume Amazon sellers |
| Temu courier (direct)MaxInvent | Temu orders — subsidised rate | Small parcels under 2kg |
Typical UK multi-channel seller connects 4-5 of these plus any specialist couriers (e.g. hazmat, temperature-controlled) to get real rate-shopping leverage.
Why Temu courier in the rate-shopping mix matters
Temu sells a lot of orders at low average-order-value under 2kg. Temu has negotiated bulk courier contracts and passes a subsidised rate to sellers through its seller portal. For those parcels, Temu's courier rate is typically 20-40 pence cheaper than Royal Mail small-parcel or Evri. On 200 Temu orders a day, that's roughly £40-80/day in courier savings, every day.
The catch: Temu's courier rate is only accessible via Temu's seller portal or Temu's direct API — it isn't reachable through any other courier's aggregator. Based on publicly available product documentation at the time of writing, MaxInvent is the only UK inventory platform that integrates the Temu courier API directly, so Temu's rate is included in rate shopping for Temu orders automatically. Other platforms force dispatchers into the Temu seller portal to buy the label manually.
Rules that make rate shopping actually useful
Pure “always pick cheapest” is a trap — cheap couriers have higher damage and later delivery than premium couriers, and SLA breaches cost more than the saving. Realistic rule patterns:
- Order value thresholds. Under £20 net: cheapest tracked. £20-£100: cheapest with insurance over £50. Over £100: signature-required services only.
- Weight bands. Under 2kg: Royal Mail / Evri / Temu. 2-10kg: DPD or Evri. 10kg+: DPD or Parcelforce only. Over 30kg: palletised carrier.
- SKU-level exclusions. Fragile SKUs exclude Evri. Hazmat SKUs exclude Royal Mail air. Oversize SKUs exclude anything with a 1.2m max.
- Destination rules.Northern Ireland: specific carrier allow-list. EU: Royal Mail International or DPD Europe only. Highlands & Islands: exclude couriers that surcharge.
- Channel rules. Amazon Prime orders: Amazon Shipping preferred. Temu orders: Temu courier preferred. TikTok Shop: use the SLA implied by the listing.
How to evaluate this during a platform trial
- Export 100 recent real orders (mix of small, medium, large plus a few international and a few heavy).
- Connect two of your real courier accounts to the trial platform. Not platform rates — your own.
- Generate labels for those 100 orders through the platform, letting it pick the courier.
- Compare total spend against what you'd have paid using your usual default.
- Separately measure: how long does the platform take to return a rate? Under 2-3 seconds per label is acceptable. Over 10 seconds will slow your dispatch team down.
Where MaxInvent fits
MaxInvent supports live API rate shopping with your own courier contracts — zero mark-up on any bring-your-own account. Royal Mail, DPD, Evri, Parcelforce, Amazon Shipping and Temu courier direct are all native. The rules engine supports weight, size, SKU attribute, destination and channel rules independently. Rates are returned in under 2 seconds per label for typical UK carriers. If you'd like to see it on your own orders and courier contracts, book a 30-minute demo.
References to Royal Mail, DPD, Evri, Parcelforce, Amazon Shipping and Temu courier on this page describe publicly documented service characteristics at the page's last-updated date. MaxInvent is an independent UK company and has no affiliation, endorsement or partnership with any of these carriers. Rate cards, service coverage and API behaviours change regularly — always confirm current pricing and capabilities with each carrier directly before making contract decisions.