The answer depends almost entirely on three variables: how many items are in the order, whether it’s a split shipment, and how the customer would have otherwise gotten to the store. Get those three things right, and e-commerce’s carbon footprint is roughly half that of in-store shopping. Get them wrong, and the advantage disappears.
A research comparison of brick-and-mortar, bricks-and-clicks, and pure-play online retail found traditional stores carry a carbon footprint 17% higher than online channels, but that advantage is contingent on how the online operation is actually run.
Where E-Commerce Loses Its Carbon Advantage
Last-mile delivery is e-commerce’s highest carbon exposure. The final leg of delivery (the van driving individual packages to individual addresses) is significantly less efficient per item than consolidating those trips through a customer’s single store visit. When customers order one item at a time, get same-day delivery, or receive split shipments, the carbon math shifts against online retail.
The fix exists: ordering multiple items in a single transaction reduces per-item emissions by more than 30%. Consolidating split shipments cuts shipping costs and emissions simultaneously. Offering customers a longer delivery window (with a visible carbon benefit as the incentive) has tested well in several pilots.
The energy footprint of e-commerce’s physical infrastructure (warehouses, data centers, server farms processing transactions) is real but manageable. High-efficiency warehouse design and renewable energy purchasing are available options. The logistics chain is where the substantive decisions happen.
What Sustainable E-Commerce Actually Looks Like
The retailers making real progress on e-commerce emissions share a few operating practices: they’ve invested in demand forecasting to reduce split shipments, they’ve right-sized their packaging, and they’ve built delivery consolidation into their fulfillment logic.
Right-sizing packaging alone can produce meaningful results. One company redesigned laundry detergent packaging to be lighter and smaller, reducing its carbon footprint by 1,200 tons annually while cutting shipping costs. That’s not a sustainability project: it’s a logistics optimization with an environmental benefit.
Fleet electrification is the next step for companies with significant last-mile delivery volume. Electric vehicles reduce per-delivery emissions substantially, and as fleet costs continue to fall, the economics are becoming straightforward for companies operating at scale.
The most sustainable e-commerce operation is the one that treats logistics efficiency as a carbon strategy — not the one with the greenest marketing copy.
The Brick-and-Mortar Advantage Nobody Talks About
Physical retail has one sustainability advantage that rarely gets discussed: customer consolidation. A single store serves hundreds of customers with one set of facilities, one lighting system, one HVAC system. E-commerce replicates those facilities per customer, distributed across a delivery network.
This doesn’t make physical retail automatically better: the customer driving solo to a store offsets most of that advantage. But it does mean that the most environmentally sophisticated retailers are using physical stores as consolidation points: click-and-collect programs, in-store returns, and localized inventory that reduces long-distance shipping.
The hybrid model, where customers collect online orders from a physical location, is consistently the lowest-carbon retail option available. It combines the logistics efficiency of consolidated delivery with the convenience of online ordering.
P.S. If you’re running an e-commerce operation and haven’t yet audited your split shipment rate, that’s where to start: it’s the single metric most correlated with unnecessary packaging and delivery emissions.