Objectives To describe firearm storage practices among US adults and examine the relationship between having received formal firearms training and firearm storage.

Methods In 2015 we asked a nationally representative online sample of 2072 gun owners how they stored household firearms, their reasons for owning guns, the number and types owned, had they carried a loaded handgun in the prior month and whether they had formal firearms training (and if so, whether training covered suicide prevention, accident prevention, firearm theft prevention, safe handling and safe storage). Unadjusted associations between gun owner characteristics and storage practices were estimated using Pearson’s χ² tests; adjusted associations used multivariate logistic regressions. Final survey weights that combined presample and study-specific poststratification weights account for oversampling of firearm owners and survey non-response.

Results 29.7% (95% CI 27.4% to 32.1%) stored ≥1 firearm loaded and unlocked. Of the 61.4% (95% CI 58.9% to 63.9%) of gun owners with firearms training, 32.3% (95% CI 29.4% to 35.3%) stored ≥1 firearm loaded and unlocked, compared with 25.8% (95% CI 22.3% to 29.7%) of those without training. Storage did not differ by training component, age, sex or race. However, firearms were more likely stored loaded and unlocked when respondents owned for protection, owned >1 firearm, owned handguns or carried a loaded gun. After adjusting for firearm-related characteristics, firearms training was not associated with storing firearms loaded and unlocked (adjusted OR=1.11, 95% Cl 0.80 to 1.53).

Conclusion Firearms training, as currently provided, is unlikely to reduce unsafe firearm storage.