This study aims to analyze how upstream oil and gas businesses in Nigeria manage their operating costs and how it impacts their financial performance. It examines the effects on net profit margins of budgeting, cost reduction, operational efficiency improvements, and expenditure monitoring in a capital-intensive and highly volatile industry. This study employs a quantitative approach by examining secondary data collected from ten selected upstream oil businesses between 2019 and 2023. To examine the data, we used descriptive statistics, multiple regression, and correlation. The four methods contributed significantly to the increase in earnings, but operational efficiency had the most impact. Keeping track of your expenditure, sticking to your budget, and finding methods to save money might lead to much higher income. Improving financial performance and keeping profits high in the face of rising operational expenses and crude oil prices requires strategic management operations to include effective ways of cost control. Upstream oil and gas businesses in Nigeria need to keep expenses down if they want to generate money. Firms must improve their planning, constantly reduce costs, simplify processes, and monitor their spending, according to the study.