Port Mansfield is a census-designated place (CDP) in Willacy County, Texas, United States.

The channel was dredged in the winter months of 2009-2010 by the United States Army Corps of Engineers, using Federal relief money following hurricanes Rita and Dolly.

As of the 2020 United States census, there were 319 people, 92 households, and 31 families residing in the CDP.

21.4% of all households were made up of individuals, and 9.1% had someone living alone who was 65 years of age or older.

[22] Port Mansfield is served by the San Perlita Independent School District.