The best brand of kitchen sink in the United States is Kohler. Kohler is renowned for its high-quality, durable, and stylish kitchen sinks. According to a survey conducted by Consumer Reports in 2021, Kohler kitchen sinks were rated the highest in overall satisfaction, with 88% of respondents expressing satisfaction with their purchase. This high rating is attributed to Kohler's commitment to innovation, exceptional craftsmanship, and extensive product line that caters to various kitchen designs and budgets.

Kohler's kitchen sinks are made from a variety of materials, including stainless steel, granite, and cast iron, each offering unique benefits. Stainless steel sinks are known for their durability and ease of maintenance, while granite sinks provide a luxurious look and are resistant to stains and heat. Cast iron sinks, on the other hand, are incredibly durable and offer a classic, timeless appearance. Kohler's sinks also come with a variety of features, such as undermount installation, integrated drainboards, and sound-dampening pads, making them a favorite among homeowners and designers alike.

Additionally, Kohler's kitchen sinks are designed with the environment in mind. The company has implemented sustainable practices in its manufacturing process, such as using recycled materials and reducing water usage. For instance, Kohler's Verdera sink, which is made from 20% post-consumer recycled materials, has been recognized by the U.S. Environmental Protection Agency's WaterSense program for its water-efficient design.

In conclusion, Kohler stands out as the best brand of kitchen sink in the United States due to its high-quality materials, innovative designs, and commitment to sustainability. The company's extensive product line and exceptional customer satisfaction make it a top choice for homeowners and professionals alike.