In two primary care clinics in Texas serving low-income patients, systolic blood pressure (SBP) trajectory was examined during 2 years in patients with diabetes mellitus (mean SBP ≥140 mm Hg: 152 mm Hg±11.2 in the baseline year). Among 860 eligible patients, 62.0% were women, 78.8% were Hispanic, and 41.2% were uninsured. Overall, SBP dropped 0.56 mm Hg per month or 13.4 mm Hg by 24 months. For patients with mean glycated hemoglobin ≥9% in year 1, SBP declined 4.8 mm Hg less by 24 months vs those with glycated hemoglobin <7% (P=.03). Compared with white women, SPB declined 7.2 mm Hg less by 24 months in Hispanic women (P=.03) and 9.6 mm Hg less by 24 months in black men (P=.04). SBP also declined 9.1 mm Hg less by 24 months for patients taking four or more blood pressure drug classes at baseline vs one drug class. In this low-income cohort, clinically complex patients and racial-ethnic minorities had clinically significantly smaller declines in SBP.