This policy-oriented article examines the impact of transportation-infrastructure development on Iran’s key macroeconomic variables during the period 2001–2023 (1380–1402 in the Iranian calendar). The composite transportation index covers the road, rail, maritime, and air sectors, while the economic variables include non-oil GDP, unemployment rate, inflation, exchange rate, money supply, and the overall stock-market index.



The research methodology combines Ordinary Least Squares (OLS) regression, the Granger causality test, and the Engle–Granger cointegration test, using annually collected data.



Findings show that transportation development significantly boosts economic growth (non-oil GDP), reduces unemployment, and helps moderate inflation. These results highlight transportation-infrastructure investment as a key driver of production growth and job creation.



The outcomes are practical for policymakers in civil engineering, transportation, and urban development. Coordinated improvements across road, rail, maritime, and air transport can also contribute to relative exchange-rate stability and liquidity control. The study recommends prioritizing transportation projects and enhancing efficiency to harness the sector’s potential for sustainable economic growth, improved social welfare, reduced unemployment, and greater macroeconomic stability.