BackgroundChild undernutrition is a major public health problem and an important indicator of child’s health. Adequate nutrition is critical for a child’s growth and development. Growth monitoring and promotion (GMP) services is a nutrition intervention aimed at improving the nutritional status of children. We assessed the utilization of growth monitoring and promotion services and nutritional status of children less than two years of age in northern Ghana.MethodsThis was a descriptive cross-sectional study that involved face-to-face interviews among 266 mothers with children < 2 years of age attending child welfare clinics (CWC). We also collected anthropometric measurements. Descriptive statistic was performed and data presented as percentage. The nutritional status of children was classified as underweight (weight-for-age z score < -2 standard deviations), stunted (length-for-age Z score < − 2) and wasted (weight-for-length z score < -2) while utilization of GMP services was based on attendance to CWC and ability to interpret different growth curves. Chi square test was used to determine the relationship between utilization of GMP services and nutritional status of children at an alpha of 0.05.ResultsThe prevalence of undernutrition shows that, 18.6% of the children were underweight, 14.7% were stunted and 7.9% were wasted. About 60% of the mothers accessed GMP services regularly. Less than half of the mothers were able to interpret the children’s growth curve correctly: falling growth curve (36.8%), flattening growth curve (35.7%) and rising growth curve (27.4%). In combining children < 6 and 6–23 months of age, only one-third (33.1%) of mothers practiced appropriate infant and young child feeding. Regular GMP services was found to have a statistically significant relationship with underweight (P < 0.001), stunting (P = 0.006) and wasting (P = 0.042).ConclusionThe level of undernutrition remains high and child feeding practices is poor. Maternal utilization of GMP services is also low in the study area. Similarly, ability to interpret the child’s growth curve appropriately persist as a challenge among women. Thus, attention is needed to improve utilization of GMP services to address child undernutrition challenges.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40795-023-00729-6.