The HSK test (see https://en.wikipedia.org/wiki/Hanyu_Shuiping_Kaoshi for background information and http://www.chinesetest.cn/goKdInfoOrPlan.do for the testing center) is available through the following sites on the US mainland. Please contact the site of your choosing to arrange to take the test, if you are interested.
1. Phoenix Tree Test Center
Contact email: ssheng@phoenixtree.com
Test dates: 9/11/2021, 10/17/2021
2. Nihao Chinese LLC.
Email: hsk@nihaocac.com
Test date: 9/11/2021
3. Center for Chinese Education Services in North America
Email: laoha168@gmail.com
Test date: 10/17/2021
4.Global Village Academy, Douglas County (IBT)
Email: sbush@gvaschools.org
Test date: 10/17/2021
5. Confucius Institute at the University of Central Arkansas (Internet-based Test)
Email: avauca@gmail.com
Test date: 10/17/2021
6. University of Kentucky (Internet-based Test)
Email: lashana.harney@uky.edu
Test date: 10/17/2021