The Boring Company Series D round, announced on Thursday, has closed at $3 billion, placing a $23 billion valuation on the tunnelling startup and marking the latest large injection of private capital into Elon Musk’s cluster of companies. The United Arab Emirates is the lead investor, and the deal comes bundled with a contract for the company to build more than 150 kilometres of tunnels across the Emirates.
The round also includes Sequoia Capital, A16z, and Baron Capital. Investors were not simply asked to write cheques: The Wall Street Journal reported last week that the company had told prospective participants they would need to help with recruiting or business development if they wanted in, a condition that Musk appeared to confirm in a post on X.
Boring Company Series D round in context: a Musk empire on the move
The fundraise fits a pattern. SpaceX raised $86 billion in a record-breaking public listing in June, and Neuralink, Musk’s brain-implant startup, was being valued as high as $42 billion on secondary markets, nearly five times the $9 billion valuation it carried in its May 2025 funding round, according to Business Insider’s earlier reporting. Investor appetite for Musk-connected ventures shows little sign of cooling.
The Boring Company was founded in 2016 after Musk announced plans on Twitter to build a tunnelling company following a spell stuck in Los Angeles traffic. Its earliest ambitions centred on hyperloop pods travelling between cities at speeds of up to 600 miles per hour. Those plans were quietly shelved or cancelled over the following decade, with proposed tunnel projects in Los Angeles, Washington DC and Chicago all coming to nothing.
What survived and scaled is the Vegas Loop, a transit network beneath Las Vegas in which passengers are shuttled through tunnels in Teslas. The company has also dug tunnels for its sister businesses, including a “Cybertunnel” for completed Cybertruck units at Tesla’s Texas gigafactory.
Vegas Loop build-out: tunnels, machines and approvals
The Vegas Loop is, by some margin, The Boring Company’s most substantial operational asset. The Boring Company states that Clark County and the City of Las Vegas have approved 68 miles of tunnel and 123 stations, cementing the network’s long-term scope. The company has also been given the green light to build similar systems in Nashville and Dubai.
The scale of what has already been built is considerable. According to Basenor, by mid-2026 The Boring Company had completed more than 51 kilometres (31.7 miles) of tunnels beneath Las Vegas, connecting the Convention Center, Resorts World, Allegiant Stadium and multiple Strip venues. That figure underlines how much ground has already been covered, even as the approved network remains less than half built.
Progress on individual tunnel drives has also been accelerating. Basenor reports that in March 2026 the company’s Prufrock-2 boring machine completed a 2.28-mile (3.67 km) tunnel near Westgate Las Vegas, the longest single Vegas Loop tunnel drive on record, edging past the previous internal record of 2.26 miles. The incremental margin is narrow, but Prufrock-class machines are central to the company’s claim that it can drive tunnels faster and at lower cost than the industry norm, so each benchmark matters to the investment case.
The UAE contract announced alongside the Boring Company Series D round suggests the company is now pitching its model internationally in earnest, moving beyond the single-city demonstration it has been running in Las Vegas. Whether the Vegas Loop’s Tesla-shuttle approach translates to the scale and passenger volumes a 150-kilometre UAE network would require is a question the fresh capital will need to help answer. The next test of the methodology is no longer hypothetical: the contracts are signed and the drilling schedule will follow.