What testosterone level is low enough to need treatment?

Short answer

• You generally need both symptoms of hypogonadism and consistently low morning total testosterone. Most guidelines use a cutoff of about 300 ng/dL (10.4 nmol/L) — i.e., consider treatment when symptoms are present and total testosterone is <300 ng/dL on at least two separate morning tests.

Details and practical points

• Symptoms matter: low libido, erectile problems, low energy, depressed mood, loss of muscle mass, or low bone density are common reasons to test and consider treatment. A low number alone without symptoms usually does not merit lifelong testosterone therapy.
• Testing: measure total testosterone in the morning (ideally 7–10 AM), fasting if possible, and repeat the test because levels fluctuate. If the first result is borderline, repeat it and consider measuring free or bioavailable testosterone.
• Borderline/ambiguous ranges: If total T is in a gray zone (roughly 230–350 ng/dL, lab-dependent), measure free testosterone (calculated or equilibrium dialysis) and check sex‑hormone binding globulin (SHBG). In conditions that change SHBG (obesity, diabetes, liver disease), free T is more informative.
• Primary vs secondary hypogonadism: check LH and FSH. High LH/FSH suggests primary testicular failure; low/normal LH/FSH suggests hypothalamic/pituitary (secondary) causes and often needs pituitary evaluation.
• Risks and contraindications: testosterone therapy can suppress sperm production (causing infertility), raise hematocrit (risk of clotting), worsen untreated sleep apnea, and has nuanced effects on cardiovascular and prostate health. Active prostate or breast cancer is an absolute contraindication.

Next steps

• If you have symptoms, ask your primary care doctor to order morning total testosterone (and if borderline, free T + SHBG). If low on repeat testing, referral to an endocrinologist or urologist experienced in male reproductive health is appropriate.

Services/brands you can use

• Lab testing: Quest Diagnostics or LabCorp — widely available, reliable morning testosterone draws.
• Specialist care: Mayo Clinic or Cleveland Clinic Men’s Health/Endocrinology — good for complex evaluation or if you want a high-level specialist opinion.
• Telehealth options (convenient for initial evaluation, but be sure they provide appropriate testing and follow-up labs): Hims and Roman — convenient for ordering tests and starting therapy, but confirm they will do baseline labs and monitor hematocrit, PSA, and symptoms regularly.

Reference

• Endocrine Society clinical practice guideline (most recent adult guideline uses ~300 ng/dL as the diagnostic threshold when symptoms are present).

If you want, tell me any symptoms you’re having and your most recent testosterone lab (include units and time of day when drawn) and I can help interpret it and recommend next steps.