Vertical Integration

Elon Musk's companies make the hard parts of their products in-house instead of buying them from suppliers, a strategy business schools call vertical integration. For SpaceX that means building its own rocket engines and avionics. For Tesla it means designing its own self-driving chips and battery cells and casting its own car bodies on giant presses. Owning the part means owning how fast it can change and what it costs.

What is Vertical Integration?

Most carmakers buy chips, battery cells, and other major pieces from specialist suppliers, and older launch companies buy their engines, then bolt the pieces together. A vertically integrated company pulls the critical pieces in-house. That is harder and more expensive at the start, because the company has to build the factory and learn the craft from scratch. The payoff is control: no supplier sets the price, the timeline, or the pace of improvement.

Why It Matters to Elon Musk

SpaceX was pushed into it from the start. In 2001 and 2002 Elon Musk tried to buy refurbished missiles in Russia and came home without a deal, put off by the prices. SpaceX hired engineers and built its own rockets instead. The habit that came out of those trips has its own name, the idiot index: the cost of a finished part divided by the cost of its raw materials, which flags the parts worth making in-house.

How it Works in Practice

At SpaceX the engine is the clearest case. SpaceX designs the Raptor at its own facilities, 3D-printed its turbopumps and injectors early on, and casts its manifolds from superalloys it developed in-house. Because the engine belongs to SpaceX from end to end, the team can change a design and fire the new version on the test stand on its own schedule.

Tesla applies the same thinking to cars. It designs its self-driving computer, and Samsung and Taiwan Semiconductor Manufacturing Company (TSMC) manufacture the chips. Tesla buys most of its battery cells from Panasonic, LG Energy Solution, and Contemporary Amperex Technology (CATL), and it designed the larger 4680 cell and builds it on its own lines in Texas and California. Instead of welding a rear underbody together from dozens of stamped pieces, it casts the whole section in one piece on a giant press.

The Evidence

When Tesla unveiled its self-driving computer at Autonomy Day in April 2019, it reported 2,300 frames per second of image processing against 110 on the bought hardware it replaced, about 21 times faster.

The casting story is about deletion. A rear underbody that used to be put together from about 70 separate stamped and welded pieces became one aluminum casting, which Tesla said cut that section's production cost by about 40 percent. At Battery Day in September 2020 Tesla said front and rear castings joined by a structural battery pack would remove hundreds more parts from the car.

SpaceX shows the same pattern across a whole rocket. It makes its own engines, avionics, and structures and builds most of each rocket in-house, where the launch industry's norm is to buy major parts and assemble them.

Vertical Integration Today

The principle runs through every Elon Musk company. SpaceX builds the Starlink satellites it launches along with the rockets that carry them, and Tesla trains its driving software on computers it owns. Wherever a supplier controls the price or the pace of a part that matters, the companies have learned to make that part.

What Comes Next

The next frontier is the chip. On March 21, 2026 Elon Musk unveiled TERAFAB, a planned chip factory that Tesla and SpaceX will build together to make artificial intelligence (AI) processors on a 2-nanometer process instead of relying on outside chipmakers. The same logic now reaches software: MACROHARD, a joint Tesla and SpaceXSI project to run a software company on AI agents, is designed to run on Tesla's AI4 car chips and SpaceXSI's Colossus supercomputers. The goal is to own whichever part is too costly, too slow, or too important to leave in someone else's hands.

The Bottom Line

Vertical integration costs more at the start and asks a company to master work its rivals buy. For a reusable rocket and a cheaper electric car, Elon Musk's companies decided that owning the engine, the chip, and the casting was worth that cost, and in 2026 they extended the bet to a chip factory of their own.