Background
Source of potable water has implication on the population health. Availability of Improved Drinking Water Sources (IDWS) is a problem in developing countries, but variation exists across segments of the population. This study therefore examined the relationship between wealth status, sex of household head and source of potable water.

Methods
The 2013 Nigeria Demographic and Health Survey data was used. A representative sample of 40,680 households was selected for the survey, with a minimum target of 943 completed interviews per state covering the entire population residing in non-institutional dwelling units in the country. Households where information on drinking water sources was not reported were excluded, thus reducing the sample to 38021. The dependent and key independent variables were IDWS and Wealth Index respectively. Data were analysed using Chi-square and binary logistic regression (α = .05).

Results
Households that used IDWS were headed by females (66.7 %) than males (58.7 %). Highest proportion of households who used IDWS was found in the rich wealth index group (76.7 %). The likelihood of using IDWS was higher in household headed by females (OR = 1.41; C.I = 1.33–1.49, p <0.001). Households that belong to rich wealth index and middle class were 5.06(C.I = 4.81–5.32, p <0.001) and 2.62(C.I = 2.46–2.78, p <0.001) respectively times more likely to IDWS than the poor. This pattern was sustained when other confounding variables were introduced into the regression equation as control.

Conclusions
Households headed by women used improved drinking water sources than those headed by men. However, wealth index has strong influence on the strength of relationship between sex of household head and improved drinking water sources.