Background— A simple and effective heart failure (HF) risk score would facilitate the primary prevention and early diagnosis of HF in general practice. We examined the external validity of existing HF risk scores, optimized a 10-year HF risk function, and examined the incremental value of several biomarkers, including N-terminal pro-brain natriuretic peptide. Methods and Results— During 15.5 years (210 102 person-years of follow-up), 1487 HF events were recorded among 13 555 members of the biethnic Atherosclerosis Risk in Communities (ARIC) Study cohort. The area under curve from the Framingham-published, Framingham-recalibrated, Health ABC HF recalibrated, and ARIC risk scores were 0.610, 0.762, 0.783, and 0.797, respectively. On addition of N-terminal pro-brain natriuretic peptide, the optimism-corrected area under curve of the ARIC HF risk score increased from 0.773 (95% CI, 0.753–0.787) to 0.805 (95% CI, 0.792–0.820). Inclusion of N-terminal pro-brain natriuretic peptide improved the overall classification of recalibrated Framingham, recalibrated Health ABC, and ARIC risk scores by 18%, 12%, and 13%, respectively. In contrast, cystatin C or high-sensitivity C-reactive protein did not add toward incremental risk prediction. Conclusions— The ARIC HF risk score is more parsimonious yet performs slightly better than the extant risk scores in predicting 10-year risk of incident HF. The inclusion of N-terminal pro-brain natriuretic peptide markedly improves HF risk prediction. A simplified risk score restricted to a patient’s age, race, sex, and N-terminal pro-brain natriuretic peptide performs comparably to the full score (area under curve, 0.745) and is suitable for automated reporting from laboratory panels and electronic medical records.