What Duolingo score do you need for Sam Houston State University?

The checklist lists the test as Duolingo English Test (DET/EPT). It applies when English is not your first language and your high school or previous college is not on SHSU's list of official English language nations.

The page states no Duolingo validity period or subscore rule.

For comparison, the same checklist sets IELTS at 6.0 or higher.

Other ways to qualify include successful completion of an intensive English programme recognised by SHSU or TIEC, a C or better in English Composition I at a regionally accredited US college, and qualifying ACT or SAT verbal scores. Waivers may be considered for applicants taught in English.

Requirements vary by programme and change between admissions cycles. The score that binds you is the one on your Sam Houston State programme page and in your offer letter, so check it there before you book a test.