> ## Documentation Index > Fetch the complete documentation index at: https://docs.vortexiq.ai/llms.txt > Use this file to discover all available pages before exploring further. # Catalogue Drift vs Amazon UK, OnBuy > Same SKU listed at materially different prices on OnBuy vs Amazon UK. MAP/brand-consistency risk. How to read it, why it matters, and how to act on it. **Metrics type:** [Cross-Platform Metrics](/nerve-centre/overview#metrics-types-explained) • **Category:** [Marketplace](/nerve-centre/connectors#connectors-by-type) > Same SKU listed at materially different prices on OnBuy vs Amazon UK. MAP/brand-consistency risk. ## At a glance > Count of SKUs that are listed on both OnBuy and Amazon UK but priced more than 15% apart. A brand-consistency and MAP-policy risk: if Amazon's price-policing crawler spots the cheaper OnBuy listing, the merchant's Amazon listing can be suppressed under "Featured Offer disqualification" rules, costing more revenue than the OnBuy listing makes. | | | | -------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **What it counts** | `COUNT(SKUs WHERE listed on both AND ABS(onbuy.price - amazon.price) / onbuy.price > 0.15)`. Drift is symmetric, OnBuy can be cheaper or more expensive; either direction triggers the count. | | **Direction skew** | OnBuy is cheaper than Amazon for \~80% of drifted SKUs in our sample. OnBuy commission (5 to 9%) is lower than Amazon (15%), so merchants who simply pass commission savings through to price end up cheaper on OnBuy. This is the MAP risk vector. | | **Source data** | OnBuy `GET /v2/listings` (current price field) joined to Amazon SP-API `Listing.attributes.list_price` for the UK marketplace `A1F83G8C2ARO7P`. | | **Match key precedence** | (1) GTIN / EAN / UPC where available, (2) seller\_sku, (3) manual ASIN cross-reference on the OnBuy listing. Match precision is the same as `onbuy_xc_missing_on_onbuy`. | | **Drift threshold** | 15% absolute price gap. Below 15% is treated as normal price-discovery noise (rounding, occasional promo); above 15% is treated as a structural pricing issue requiring action. | | **Currency** | GBP only on both sides. Non-GBP Amazon listings (e.g. on `A1PA6795UKMFR9` for DE) are excluded. | | **What "drift" really measures** | Price drift only, not title or image drift. Title and image divergence are surfaced separately under [`shopline_xc_catalogue_drift`](/nerve-centre/kpi-cards/shopline/catalogue-drift-vs-amazon) for the Shopline equivalent; OnBuy's API does not yet expose image hashes for cross-platform comparison. | | **Time window** | `30D` rolling. Window is used to apply a stability filter, a SKU is only counted as drifted if its price gap has held >15% for at least 7 consecutive days, to avoid flagging deal-day fluctuations. | | **Alert trigger** | `>10 SKUs drifting >15%`. The integer threshold reflects scale; 1 to 10 drifted SKUs is normal noise; above 10 is a process issue. | | **Roles** | owner, marketing. | | **Only when** | `has_amazon_sibling = true`. | ## Calculation Calculated automatically from your OnBuy data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading. ## Worked example **A small UK kitchen-and-tableware seller, snapshot taken 27 Apr 26.** The seller has 95 SKUs listed on OnBuy and 180 on Amazon UK. The matcher finds 78 SKUs listed on both. The drift comparison flags 14 SKUs above the 15% threshold: | SKU | OnBuy price | Amazon UK price | Gap | Cheaper on | | --------------------------------- | ----------- | --------------- | ------ | -------------------------- | | KT-2104 (oak chopping board) | £18.99 | £24.99 | -24.0% | OnBuy | | KT-2118 (linen tea-towel set) | £14.50 | £19.99 | -27.5% | OnBuy | | KT-2202 (wooden serving platter) | £29.99 | £39.99 | -25.0% | OnBuy | | KT-2450 (cast-iron skillet) | £42.00 | £52.00 | -19.2% | OnBuy | | KT-3201 (ceramic mug, navy) | £8.99 | £11.99 | -25.0% | OnBuy | | KT-3210 (ceramic mug, sage) | £8.99 | £12.50 | -28.1% | OnBuy | | KT-3215 (espresso cups, set of 4) | £24.99 | £34.99 | -28.6% | OnBuy | | KT-3224 (cereal bowl, set of 4) | £21.99 | £29.99 | -26.7% | OnBuy | | KT-3301 (storage jar, large) | £16.99 | £19.99 | -15.0% | OnBuy (right at threshold) | | KT-4102 (pasta bowl, white) | £39.99 | £29.99 | +33.3% | Amazon | | (... 4 more rows ...) | | | | | ```text theme={null} SKUs listed on both 78 Drifted >15% 14 Of which OnBuy cheaper 12 (86%) Of which Amazon cheaper 2 (14%) ``` **What it means for this seller.** 14 drifted SKUs is above the alert threshold (10). The pattern is unmistakable: 12 of the 14 are cheaper on OnBuy by 19 to 29%. The merchant is passing the OnBuy commission saving (\~7%) plus an additional 12 to 22% straight to the buyer, presumably to be price-competitive on the smaller marketplace. The risk is real and immediate. Amazon's pricing crawler scans OnBuy weekly. When it finds a 25% cheaper listing on OnBuy with matching EAN, the Amazon listing's "Featured Offer" (Buy Box) can be suspended under the "Fair Pricing" policy. For a merchant doing £40k / month on Amazon vs £6k / month on OnBuy, losing the Amazon Buy Box for even one of these SKUs (KT-2104 was the seller's #3 SKU on Amazon at £980 / 30D) costs roughly 30 to 50% of that SKU's Amazon revenue, vastly more than the additional OnBuy margin made by being 24% cheaper. The action is to lift OnBuy prices by 15 to 20% on the 12 cheaper SKUs to bring the gap inside the 15% safety band. The merchant will lose roughly 10 to 15% of OnBuy unit volume but stay safe on Amazon Buy Box, which is the right trade. ## Sibling cards merchants should reference together This card is the marketplace-vs-marketplace pricing-discipline read. The natural pairings: | Card | Why it matters next to drift | What the combination tells you | | -------------------------------------------------------------------------------------------------------- | --------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------- | | [Amazon UK Top SKUs Missing on OnBuy](/nerve-centre/kpi-cards/onbuy/amazon-uk-top-skus-missing-on-onbuy) | The "what to add" twin. | Drift fixes the listings already shared; missing-on-OnBuy adds the ones not yet shared. The two cards together form a complete OnBuy catalogue audit. | | [OnBuy vs DTC Price Gap](/nerve-centre/kpi-cards/onbuy/onbuy-vs-dtc-price-gap) | The DTC twin. | If OnBuy is cheaper than both DTC and Amazon, the merchant is treating OnBuy as a deep-discount channel; rationalise pricing or accept the cannibalisation. | | [OnBuy Commission % of Revenue](/nerve-centre/kpi-cards/onbuy/onbuy-commission-of-revenue) | The fee context. | OnBuy's lower commission tempts merchants to drop OnBuy prices; this card shows when that habit has grown into a MAP risk. | | [Listings Discounted >20%](/nerve-centre/kpi-cards/onbuy/listings-discounted-20) | OnBuy-side discounting view. | If the same SKUs show on both this card and Listings Discounted, the price is structurally low on OnBuy, not just drifted vs Amazon. | | [Avg Discount vs RRP](/nerve-centre/kpi-cards/onbuy/avg-discount-vs-rrp) | The average view. | A high average discount on OnBuy with high drift count = OnBuy is the merchant's discount channel by default. | | [Amazon UK Total Revenue](/nerve-centre/amazon/amazon_total_revenue) | The downside risk. | Quantifies what is at stake if Amazon Buy Box gets suspended (typical 30 to 50% revenue hit per affected SKU). | | [OnBuy Total Revenue](/nerve-centre/kpi-cards/onbuy/total-revenue) | The upside being chased. | Lets you size whether the additional OnBuy margin from being cheaper actually exceeds the Amazon risk (usually no). | | [Catalogue Drift vs Amazon (Shopline)](/nerve-centre/kpi-cards/shopline/catalogue-drift-vs-amazon) | The DTC-Amazon twin of this card. | If both Shopline and OnBuy show drift vs Amazon, the merchant has a brand-wide MAP discipline issue, not OnBuy-specific. | ## Reconciling against the vendor's own dashboard **Where to look in OnBuy's own dashboard:** Neither OnBuy nor Amazon offer a built-in cross-platform pricing comparison; this is a Vortex IQ-only view. The closest manual workflow is: > **OnBuy Seller Console (`https://seller.onbuy.com`) -> Listings -> All Listings** (export CSV with prices) > **Amazon Seller Central -> Inventory -> All Inventory** (export "Active Listings Report" with prices) > **Compare in Excel: VLOOKUP on EAN, calculate ABS(price\_a - price\_b) / price\_a > 0.15.** Most merchants do not run this comparison until Amazon issues a "Fair Pricing" warning, at which point the listing is already suppressed and the revenue is already lost. **Why our number may legitimately differ from a manual comparison:** | Reason | Direction | Why | | --------------------------------- | ---------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Stability filter** | Ours lower | We require the >15% gap to hold for at least 7 consecutive days before counting. A manual snapshot will catch deal-day flash-sales that we filter out. | | **Match key precedence** | Either | Manual comparisons usually match on seller-SKU; we match on EAN/UPC first. SKUs with EAN matches that have different SKU codes per channel are flagged by us but not by manual SKU-only comparison. | | **Variant rollup** | Marginal | Amazon parent-ASINs with multiple child variants (size, colour) are flattened to per-variant rows; OnBuy listings are also per-variant. The variant tree shape matches in most categories but differs occasionally for apparel and footwear. | | **Time zone for "current price"** | Marginal | Both sides update prices through the day; we snapshot at sync time (every 6h for prices). A manual export taken at a different time of day can show a slightly different gap on SKUs the merchant is actively repricing. | | **Promo eligibility** | Either | Amazon "Buy Box" price often reflects an active promo discount that does not appear in the listing's `list_price` field. Our matcher uses `list_price` not `featured_offer_price`, which can under-count drift if the merchant runs heavy Amazon Lightning Deals. | | **Restricted brand listings** | Ours lower | Amazon listings restricted under a brand-registry policy (where the merchant cannot freely reprice) are excluded from drift detection because the merchant cannot act on them. | **Internal identity:** `onbuy_xc_catalogue_drift = COUNT(SKUs WHERE EXISTS(onbuy.listing) AND EXISTS(amazon.listing) AND ABS(onbuy.price - amazon.price) / onbuy.price > 0.15 AND drift_days_consecutive >= 7)` The drift count and the per-SKU drill-down are derived from the same join; the count should always equal the row count of the drill-down table. ***
Documentation cross-reference (for agencies running multiple platforms) The "catalogue drift" archetype recurs across every commerce-plus-marketplace stack. Reference docs for peer cards: * [`shopline.shopline_xc_catalogue_drift`](/nerve-centre/kpi-cards/shopline/catalogue-drift-vs-amazon) * [`bigcommerce.bigcommerce_xc_catalogue_drift`](/nerve-centre/bigcommerce/bigcommerce_xc_catalogue_drift) * [`shopify.shopify_xc_catalogue_drift`](/nerve-centre/kpi-cards/shopify/catalogue-drift-vs-amazon) These cards run the same archetype (`catalogue_drift`) but with different source channels.
## Known limitations / merchant FAQs **What is "Amazon Fair Pricing" and how is it triggered?** Amazon's Fair Pricing Policy lets Amazon suppress a listing's Buy Box (or de-list it entirely) if the same SKU is sold materially cheaper on another well-known retailer or marketplace. The triggers are not published precisely, but our experience says >15% cheaper consistently on a high-traffic UK marketplace will eventually trip the crawler. OnBuy is on Amazon's monitored-marketplaces list. The cost of a Buy Box suspension is typically 30 to 50% of that SKU's Amazon revenue; the saving from being cheaper on OnBuy almost never offsets it. **My OnBuy listings are cheaper because OnBuy commission is lower; isn't that fair?** Yes structurally, no operationally. OnBuy commission is 5 to 9% vs Amazon's 15%, so passing that 6 to 10 pp difference through is reasonable. The drift threshold here is set at 15%, which already accommodates the fee gap with margin. Once the gap exceeds 15%, the merchant is doing more than passing fees through; they are using OnBuy as a discount channel, which is what triggers the Amazon risk. **Why is the threshold 15% and not 10% or 20%?** 15% sits comfortably above the 6 to 10 pp Amazon-vs-OnBuy fee differential and below the rough 20 to 25% threshold where Amazon's Fair Pricing crawler appears to flag listings. The middle band (10 to 15%) is where most well-managed merchants settle, large enough to pass fee savings through, small enough not to attract Amazon attention. The threshold is configurable per-merchant if a brand has a stricter MAP policy. **Can the gap go in the other direction (OnBuy more expensive)?** Yes, and the card counts both directions. OnBuy more expensive than Amazon happens for two reasons: (1) the merchant raised Amazon prices and forgot to update OnBuy (stale-listing problem), or (2) the merchant deliberately treats OnBuy as a higher-margin channel because OnBuy buyers are less price-sensitive. The risk side is lower in this direction (no Amazon Buy Box suspension) but it does cap OnBuy revenue; OnBuy buyers will simply not buy at the higher price. **My count says 12 but I do not recognise the SKUs. What should I check?** Open the drill-down view in Nerve Centre. The most common cause of "phantom" drift is a barcode mismatch: a SKU on Amazon has the wrong EAN entered, so our matcher ties it to a different OnBuy listing. The fix is to correct the EAN in Amazon Seller Central's "Edit Product" view; the next sync will re-match correctly. **How long does it take for Amazon to react after I fix the OnBuy price?** Amazon's price-policing cycle is roughly 2 to 4 weeks; reverting the OnBuy price typically clears any Buy Box suspension within that window. If a Buy Box is already suspended, the path back is to (a) lift OnBuy price, (b) wait 2 to 4 weeks, (c) if still suspended, raise it via Amazon Seller Central's "Featured Offer ineligibility appeal" with the price-history trace. **Does this card protect against MAP policy violations on the brand side?** Partially. It catches gaps that Amazon's crawler typically flags, which correlates strongly with MAP-violation risk on the brand side too. But MAP policies are brand-defined; some brands set a 5% MAP, others 20%. If the merchant resells branded goods, the merchant should set the drift threshold to the strictest applicable MAP across their brand portfolio, not the Amazon Fair Pricing rule of thumb. **My drift count is zero but I know I have cheaper OnBuy prices. Why?** The 7-day stability filter. If the price gap has held >15% for fewer than 7 consecutive days (e.g. a recent flash sale), the SKU is excluded. The card is meant to catch structural drift, not promotional pricing. If you genuinely want a same-day snapshot, use the per-SKU drill-down which has a "show all gaps" toggle. *** ### Tracked live in Vortex IQ Nerve Centre *Catalogue Drift vs Amazon UK* is one of hundreds of KPI pulses Vortex IQ tracks across OnBuy and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English. [Start for free](https://app.vortexiq.ai/login) or [book a demo](https://www.vortexiq.ai/contact-us) to see this metric running on your own data.