The concept of electrochromic glass—glass that varies its light transmission properties with the flip of a switch—has long intrigued car enthusiasts and tech-forward manufacturers alike. Now, Toyota’s flagship luxury SUV, the Century, is reigniting the conversation with its rear side windows that can shift between clear, semi-translucent, and fully opaque. This technology doesn’t just darken the glass like traditional tint; it transforms it into a privacy screen, filtering light while obscuring visibility. And with that, an important question is emerging in the automotive customization world: Could auto-dimmable glass be the future—and a threat to traditional window tinting?

Toyota’s latest iteration of the Century, which is not yet available in the U.S., features electrochromic rear windows developed by glass manufacturer AGC. The company says this is the first application of electrochromic glass in movable door windows. Unlike tinted windows that block light, AGC’s tech scatters it in a way that mimics the aesthetic of a “traditional Japanese room,” according to Toyota’s marketing materials.

Toyota’s luxury SUV, the Century, offers rear side windows that can shift between clear, semi-translucent, and fully opaque. (Photo: Art Konovalov / Shutterstock.com)

Not everyone is convinced this technology is poised to replace window tint film, especially those in the tinting industry who know the market and its consumers best.

“Ultra-Luxury Only”

Mike Burke, founder of Sun Stoppers in Matthews, North Carolina, sees electrochromic windows remaining a high-end niche for the foreseeable future. “This technology has been around for years and will eventually get less expensive. In my opinion, it will be an ultra-luxury item only,” he says.

The cost of developing and installing such a system is currently prohibitive. Integrating electrochromic glass into movable windows requires extensive durability testing, as AGC had to prove its technology could survive the wear-and-tear of repeated door use. That development curve means higher prices for manufacturers and, potentially, consumers.

Practical Considerations

Even if price weren’t a barrier, several industry pros say electrochromic tech doesn’t fully address the key reasons people seek window tint in the first place.

“Since all states are different regarding the shade the windows can be, there will always be a need for added privacy and heat rejection,” says Darrin Darling, owner of The Tint Shop Plus in Kannapolis, North Carolina.

Darling’s point speaks to the variation in tint laws by state. In states where darker tints are prohibited, customers often look to film to strike a balance between privacy and legal compliance. An electrochromic window might offer an elegant appearance but may not meet specific legal or practical needs without further regulatory clarification.

Performance vs. Affordability

Mike Leffler, owner of Mike’s Mobile Tint in Shelbyville, Indiana, highlights another concern: “Depending on the expense, I believe it could be an option when you purchase a vehicle,” he says. “If it could stop heat, IR waves, and reduce UV, it could probably take over the market, but I think the expense will be so high that many people will avoid purchasing and end up at a shop like mine.”

Leffler also notes hidden costs. “You also have to consider replacement if a window gets broken. Your insurance will increase because of this added feature, and your deductible will probably be extremely high. I think there are a lot of variables.”

This is an often-overlooked reality in conversations around automotive tech: long-term ownership costs. Window film, while not indestructible, is far less costly to repair or replace than an integrated electrochromic system.

Regulatory Roadblocks

Outside the U.S., similar challenges exist. Chris Wingard, managing director at AlpineTint in Australia, points out that regulation may stifle adoption in his market: “I’d say Australian regulations are likely to hold back any real uptake—there are strict limits on visible light transmission,” he says. “While the technology is promising, it’s not yet a practical or robust solution for our market.”

Even with variable light transmission, electrochromic glass must still comply with local standards, and enforcement agencies may need time—and education—before widespread approval follows.

Matching and Aesthetic Consistency

For some tint professionals, the problem isn’t legal or economic.It’s aesthetic. Letha Lasiter, owner of The Tint Diva in Gadsden, Alabama, voices a common customer concern: “I think it’s a fad and only useful on a few applications, like sunroofs,” she says. “Even there, half of our clients prefer a dark film. Furthermore, we cannot match the front windows to the factory back section. This will be a large drawback for many vehicle owners. I would venture to say 90% of my clients want the front and back sections matched.”

Lasiter’s insight speaks to the heart of the consumer experience. Uniformity across all windows matters, not just functionally, but visually. If electrochromic tech can’t match factory or aftermarket appearances across a whole vehicle, it may struggle to win mass appeal.

“I applaud them for continuing to play with window film and glass alterations,” says Lasiter, but she adds: “The juice just ain’t worth the squeeze.”

Conclusion: Competition or Coexistence?

Auto-dimmable windows are clearly a marvel of modern engineering, and their inclusion in ultra-luxury models like the Toyota Century marks a significant milestone. Among those who work with drivers every day, the consensus is that electrochromic glass is a long way from dethroning window film.

Cost, regulation, performance, and aesthetic preferences all play a role. For now, the tint industry views this emerging tech not as a direct threat but as a complement—perhaps even a curiosity—for a very select audience.