Instacart should be worried about DoorDash and Uber's new deal

DoorDash will offer Costco delivery nationwide, while Uber Eats expanded its Costco partnership to 47 states from 17, intensifying competitive pressure on incumbent partner Instacart. Costco is a strategically valuable grocery-delivery addition, with in-store visits up 18% over seven years versus roughly flat traffic at Walmart and Target. The deals advance DoorDash and Uber's push into a grocery and retail-delivery market that Uber estimates as a $1 trillion opportunity, though Instacart retains an established Costco relationship and member-credit offerings.

Analysis

The strategic value is less about delivery fees than control of a high-intent household cohort. For DASH and UBER, a warehouse-club assortment raises basket size and expands advertising inventory, but bulky, low-frequency orders can be structurally margin dilutive if fulfillment subsidies or driver wait times rise. The near-term read-through should therefore be stronger for customer acquisition, subscription retention and retail-media attach than for gross profit; investors should demand evidence of incremental contribution margin rather than headline order growth.

CART faces the clearest multiple risk because retailer concentration and perceived exclusivity underpin its defensive narrative. Even if order volume remains resilient, additional platforms weaken CART's negotiating leverage over take rates, promotional funding and ad placement over the next 1-3 quarters. The more important second-order threat is that retailers can use multi-homing to pressure CART's economics broadly, not merely on one partner relationship; this would challenge the assumption that advertising can indefinitely offset lower transactional margins.

COST likely gains convenience-led member engagement, but the earnings impact is unlikely to be material unless digital orders prove incremental to warehouse visits and renewals. A larger delivery footprint could instead expose the value proposition to price-comparison scrutiny if all-in delivered pricing meaningfully exceeds in-club prices. AMZN is not the direct loser: its differentiated risk is whether marketplace delivery networks can offer broad selection without carrying grocery inventory, reducing the strategic return on its dedicated rapid-delivery infrastructure.

Consensus may overstate a zero-sum displacement of CART. Multi-platform availability can expand the category, and CART retains its retailer software, advertising and fulfillment integrations; the bearish case requires measurable erosion in its active-order growth, transaction take rate, or retailer-funded economics. Conversely, a rapid rise in DASH/UBER grocery penetration without contribution-margin improvement would be a poor-quality growth signal and could reverse an initial positive share-price reaction.

Key Decisions for Investors

• Initiate a 3-6 month pair: long DASH and/or UBER, short CART, sized beta-neutral. The thesis is multiple divergence from weakened CART bargaining power and improved platform relevance for DASH/UBER; reassess after the next two earnings reports if CART maintains order growth and stable adjusted EBITDA margin despite competitive entry.
• Prefer UBER over DASH for a conservative expression: Uber can cross-sell grocery into a broader consumer ecosystem, while DASH offers greater upside but more sensitivity to delivery-cost inflation. Use 6-month call spreads rather than outright calls if implied volatility is elevated; take profits if grocery growth is not accompanied by sequential improvement in delivery contribution margin.
• Do not chase COST on this development alone. Add only if management identifies delivery as incremental to membership renewal, traffic or digital penetration rather than a substitution from warehouse purchasing; a widening gap between delivered and warehouse pricing would falsify the member-value upside.
• Set an earnings watch on CART for gross transaction value growth, transaction revenue take rate, advertising growth, and adjusted EBITDA guide. A guidance cut or explicit retailer pricing concessions would validate the short; durable ad growth and unchanged profitability would argue for covering the position.