Tesla Just Posted Its Best Second Quarter Deliveries Ever. Here's the 1 Number That Will Actually Move the Stock on July 22.

Tesla (NASDAQ: TSLA) investors already know the headline numbers for the second quarter. The electric vehicle and energy company said earlier this month that it delivered 480,126 vehicles during the period, up about 25% year over year and more than it has delivered in any second quarter in its history. It also deployed 13.5 gigawatt-hours (GWh) of energy storage products, up about 41% from the year-ago period.

What investors don't know yet is what those record deliveries did to Tesla's profitability. That answer arrives on Wednesday, July 22, when the company posts its second-quarter results after market close, followed by a live management webcast at 5:30 p.m. ET.

With the stock closing Wednesday at $394.46, down about 12% year to date, Tesla commands a market capitalization of about $1.5 trillion and trades at about 360 times earnings. Investors paying that kind of premium aren't buying delivery counts. They need evidence that Tesla can turn all this volume into profit.

That's why I think one line in next week's report matters more than any other: automotive gross margin excluding regulatory credit sales.

Tesla Cybercab. Image source: Tesla.

A four-quarter streak

Tesla's core profitability has quietly improved for a full year now. The company's automotive gross margin excluding regulatory credits was 12.5% in the first quarter of 2025. It climbed to 15% in the second quarter, 15.4% in the third, 17.9% in the fourth, and 19.2% in the first quarter of 2026.

That's four consecutive quarters of expansion.

This metric is worth attention because it strips out regulatory credits, the emissions credits Tesla sells to other automakers. That revenue is nearly pure profit, but it says nothing about the economics of building cars. And its contribution is shrinking anyway -- credits added 3.7 percentage points to Tesla's automotive gross margin in the first quarter of 2025, but just 1.9 points a year later.

However, there is a caveat in the streak. Tesla said its first-quarter results included one-time benefits related to warranty adjustments and tariffs, which helped both its automotive margin and its 4.2% operating margin.

So the July 22 report has to do two things at once. It has to show that the margin held up near 19% on record volume, and it has to show that Tesla managed this without one-time help.

If the margin excluding credits holds in the high teens, the bull case gets simpler. It would mean Tesla just posted its best second quarter of deliveries ever while preserving the pricing gains and cost work of the past year.

If the number steps back toward the mid-teens, the record quarter looks bought (volume achieved through discounts), and the profit story supporting a $1.5 trillion valuation arguably gets much harder to tell.

What about robotaxi and energy?

Plenty of investors will listen for other things on the call, and reasonably so.

Tesla's energy business deployed 13.5 GWh of storage in the quarter, its second-biggest quarter ever behind the 14.2 GWh it deployed in the fourth quarter of 2025. The segment carried a gross margin of nearly 40% in the first quarter, making it a meaningful profit contributor. Still, energy revenue actually declined 12% year over year in Q1, so deployments alone don't guarantee segment growth.

Then there's autonomy. Tesla ended the first quarter with 1.28 million active Full Self-Driving (Supervised) subscriptions, up 51% year over year, and it launched unsupervised robotaxi rides in Dallas and Houston in April. A subscription base growing that fast is exactly the kind of high-margin revenue the valuation needs more of, so any update on robotaxi expansion or software take rates could move the stock, too.

But those initiatives are still mostly about 2027 and beyond. The margin line shows whether today's business, the one funding all of those bets, is getting more profitable or less as it scales. At 360 times earnings, Tesla doesn't have the luxury of letting profitability drift while investors wait for autonomy.

So when the report lands on July 22, the delivery recap won't be the news -- investors already have it. The number worth finding is the automotive gross margin excluding regulatory credits. If the streak extends to five quarters without one-time help, record deliveries and improving profitability would make a powerful combination. If it doesn't, investors may opt to treat the record quarter far less kindly.

Daniel Sparks has clients with positions in Tesla. The Motley Fool has positions in and recommends Tesla. The Motley Fool has a disclosure policy.