The U.S. Bureau of Labor Statistics post 60 percent of college graduates born from 1980 to 1984 were married at age 33 (6/30/2020) provides the chart copied here.
At age 33, people with higher levels of education were more likely to be married and less likely to be cohabiting than those with lower levels of education. At the time of their 33rd birthday, 32 percent of high school dropouts, 42 percent of high school graduates with no college, 49 percent of people with some college or an associate degree, and 60 percent of college graduates were married. Twenty-eight percent of those with less than a high school diploma were cohabiting, compared with only 13 percent of those with a bachelor’s degree and higher.
For related data, see the Census Bureau Educational Attainment in the United States: 2019 Table 2. For people 25 years and over no more than 53% of those that didn’t complete at least an Associates degree here married. For those that have a Bachelor’s degree, Master’s degree, Professional degree, and Doctoral degree the percentage are 63%, 68%, 71%, and 73% respectively.