Car Companies Are Seriously Patenting Built-In Toilets Now

Chinese automaker Seres, which sells vehicles under the Aito brand, has officially been granted a utility model patent for an "automotive toilet and vehicle." The patent, number CN224104011U, was filed on April 22, 2025, and approved on April 10, 2026. It’s currently active, according to auto tech site Sanyan Tech.

So how does this thing work? The system has two main parts:

• A toilet body
• A sliding rail assembly

The fixed rail mounts to the top of the toilet unit, while a sliding rail connects directly to the car’s seat. Need to go? Just pull the toilet out from under the seat. Done? Slide it back in until it disappears. The whole setup is designed to eat up as little cabin space as possible.

Under the International Patent Classification (IPC), it falls under B60R15/04 — which covers installing sanitary gear inside vehicles.

Where it beats the competition

Online reactions have ranged from laughs to genuine confusion, but the engineering here isn't a joke. The real breakthrough? Making a toilet fit without wrecking interior space.

That’s a serious challenge in modern cars, especially EVs, where battery packs eat up floor space. Seres’ solution hides the toilet entirely under a seat, making it practically invisible when stowed. Compared to similar attempts by Polestones, Seres’ design is way more integrated and discreet. Right now, it’s being called the most practical in-car toilet design on the market.

But there’s a catch

Even with sealed lids and odor-control tricks, getting people mentally comfortable with doing their business inside a moving vehicle might be the hardest part. For many drivers and passengers, that psychological block could be a bigger hurdle than any engineering challenge.