One fifth of households in the U.S. speak a language other than or besides English at home. This rate has doubled since 1980. (these and other figures from 2018 Census surveys).
The rate in Los Angeles is 59%; East Los Angeles 88;Passaic, N.J. 78%; Providence, R.I. 50%; Germantown, Md. 46%; West Valley City, Utah 39%; Springdale, AR. 35%; and Troy, MI 34%
Languages with more than a million people who speak it at home in 2018 were Spanish (41.5 million), Chinese (3.5 million), Tagalog (1.8 million), Vietnamese (1.5 million), Arabic (1.3 million), French (1.2 million), and Korean (1.1 million). There are now more people who speak Spanish at home in the United States than in any country in Latin America with the exception of Mexico, Colombia, and Argentina.
Sources: here and here