Large e-commerce marketplaces that sell products across many categories -- from groceries to electronics to apparel -- often process transactions under a single generic 'online retail' or 'general merchandise' Merchant Category Code, regardless of what specific product was actually purchased.
This creates a common source of confusion: a cardholder buying groceries through an online marketplace might expect a grocery bonus category to apply, only to find the purchase coded as general online retail instead, earning the card's base rate rather than the elevated grocery rate.
Some marketplaces have begun splitting specific verticals (like a dedicated grocery delivery service) into their own distinct MCC, which can qualify separately for grocery bonus categories even though the parent marketplace's general purchases don't -- making it important to check whether a specific online purchase path uses a distinct MCC.
This coding inconsistency cuts both ways: purchases that seem unlikely to qualify for a bonus sometimes do, if the specific online storefront happens to be coded under a favorable MCC, meaning assumptions in either direction can be wrong without checking.
Because e-commerce MCC coding can also change over time as marketplaces restructure their processing relationships, periodically reviewing statement credits against expectations -- rather than assuming a bonus category will apply consistently forever -- catches these shifts before they cost meaningful cash back.
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The marketplace may process that purchase under a general 'online retail' MCC rather than a grocery-specific code, even though the product itself was groceries.
Yes -- marketplaces occasionally restructure how transactions are processed, which can shift which bonus categories apply without notice.