The first year of life is crucial for infant growth and development and is strongly influenced by socioeconomic status (SES), including income, employment, and housing stability. This study aimed to examine the effects of SES on infant growth in Ramsar City, Iran, from March 2022 to March 2023. Using the Morgan table and average annual birth rates, 153 singleton infants from local health networks were assessed for anthropometric indicators (height, weight, and head circumference) at birth, six months, and one year. Most families (75.8%) owned their homes. Income levels were categorized into quartiles, and employment status varied: 66.7% of families had an employed father and a stay-at-home mother, while 3.3% had both parents unemployed. Results showed that lower income significantly (P<0.05) hindered infant growth, with reduced height, weight, and head circumference. Housing stability also had a significant positive effect; infants in stable (owned) housing had better growth outcomes than those in rental housing. In contrast, parental employment status did not have a significant impact. These findings emphasize that low income and unstable housing are key barriers to optimal infant development. Addressing such disparities through improved access to healthcare, nutrition, and supportive policies is essential for promoting healthy growth in early childhood.