DoorDash Stock After the Instacart Deal: Buying the Scale Its Network Can't Supply Yet

Instacart's order value grew 15% in Q3 2026. Uber's grocery and retail business was growing about 40% as of Q2 2026. Walmart's store-fulfilled delivery grew 40% in its latest quarter. DoorDash's own US grocery is growing more than twice as fast as its restaurants. And DoorDash has just agreed to pay about $17 billion for Instacart, the slower of those businesses, so I don't think it's mainly paying for growth.

Critics call the deal a monopoly. I think that misses what's being bought too. DoorDash's network already wins grocery customers, but it can't supply enough orders per store and per warehouse soon enough to make grocery delivery cheap. That's what the $17 billion is for, and that cost advantage doesn't exist yet.

DoorDash's Q3 release is blunt about grocery after five years of trying: "the product still isn't there." Consumers, it says, "pay a premium for imperfect delivery", and "a grocery store was never set up for delivery." When DoorDash runs the inventory itself in its DashMart warehouses, it reports 99%+ accuracy and delivery more than 10 minutes faster. Here's the pitch that follows from that.

I think that's a different thing from the network effect DoorDash is known for. Its network brings a member into the app, and a member who pays for takeout will try groceries there. Over time that adds orders per store, but slowly, and Instacart adds them on day one after close. What it costs to fill a cart depends on how many orders a picker and courier can handle from one store on one trip, or how full a warehouse runs. Walmart's growth shows store picking can work, but Walmart owns the shelves, the stock data and the staff. An app picks from someone else's shelves.

Here's where I part ways with our own DoorDash analysis. It treats scale as the network counted twice, and says the deal would deepen its grocery network if it closes. That's fair for today, when neither app gets a separate scale rating. I think density is a cost advantage that has to be earned on its own, and I'd want to see the cost numbers first. Amazon said with Q3 results that it's on track to cut cost to serve per unit for a fourth straight year, so the target is moving.

Uber is the name that matters here. It's growing grocery at Walmart's delivery pace with couriers from stores, which is why I'm not arguing that an app can't grow in grocery. Its remarks don't say the 40% is organic or US-only, and Uber is buying scale of its own, with Delivery Hero pending. It doesn't report a grocery margin either, so we can't see what those orders earn. Growth isn't what's scarce. Cost is what neither app can show yet.

Instacart isn't sick, though. Its GTV over the last four quarters adds up to about $41 billion, far above Uber's $15 billion annualised, so in dollars it's still adding at least as much. The next chart also argues with me: its growth has picked up while Walmart's US e-commerce has slowed. Its orders slowed once the boost from the $10 basket minimum wore off, and bigger baskets did the rest.

The critics' best argument is about grocers and data. Lee Hepner of the American Economic Liberties Project, an anti-monopoly group, called it "a food delivery monopoly". Lindsay Owens of the advocacy group Groundwork Collaborative told Reuters it would "consolidate an alarming amount of surveillance and pricing technology in one company". FoodNavigator reports that an investigation by Consumer Reports and Groundwork found Instacart price tests could produce differences of up to 23% on certain products. A small grocer that can't build its own delivery has few other apps to turn to, and that concern is real.

For shoppers, I think the limit is that Walmart and Amazon are one tap away. PitchBook's Alex Frederick makes the same point: "The real competition is Walmart and Amazon." I'm not a lawyer and can't tell you how the FTC will draw the line.

DoorDash's free cash flow was $787 million in Q3 2026, so this is a large debt-funded bet for its size. Until it closes, a holder owns the restaurant business and DoorDash's own grocery growth, and our scores don't count Instacart. I wouldn't pay extra for a grocery cost advantage until DoorDash reports one, and it doesn't publish a grocery fulfilment cost today. Rivals also get the wait: Amazon Now is already in over 450 towns and cities worldwide as of Q3 2026.

The first reply is that the network is enough. DashPass members placed about 75% of DoorDash's US grocery and retail orders in Q2 2026, and I think membership is a big part of how it got there. DoorDash also said in that Q2 release that grocery unit economics were improving significantly. If that carries on, density arrives on its own and DoorDash overpaid. My answer is that DoorDash itself says the product isn't good enough yet, and it's choosing to pay $17 billion rather than wait. But if its grocery economics catch restaurants without Instacart, I'd give up the argument, which is why that's my test.

The second is that delivery isn't the prize. Instacart's advertising and other revenue was $331 million in Q3 2026, up 23%. Frederick argues advertising "may matter more to the investment case than delivery fees", and Walmart Connect grew 43% excluding VIZIO in the July quarter. Instacart's Q3 adjusted EBITDA of $342 million also makes the equity price about 12 times that quarter annualised. I think ads are real value, and they may justify the price. But an ad business follows purchase volume, so it also needs the delivery product to keep up with Amazon and Walmart.

The third is software, and it's where I'm least sure. Instacart's Storefront ran more than 380 grocers' online stores as of its Q4 2025 letter, and it works with more than 2,200 retail banners. Independent grocers can't build what Walmart has, so being wired into their operations could be a stickier moat than density. The risk is the one critics raise: those grocers may not want to hand more of their business to one company.

Uber reports on November 4, and Walmart reports its October quarter later this month. If Uber keeps its pace while Walmart's slows, couriers from stores look good enough for now, and I'd watch whether Uber starts talking about grocery margins. The test I care about is DoorDash's own: whether its Q3 2027 release says or shows grocery unit economics have caught its restaurants before Instacart arrives. If it does, its network supplied the density. If it doesn't say so, the test hasn't tripped, but that isn't proof I'm right either. The proof would be DoorDash publishing what a grocery order costs to fill. Until then, the moat in this deal is a forecast.