This paper analyzes the impact of uninsured idiosyncratic risk and liquidity constraints on aggregate saving in a modified standard growth model. The model incorporates individual precautionary saving motives and borrowing constraints, leading to higher aggregate saving rates compared to complete markets. The key features of the model include endogenous heterogeneity, aggregation, infinite horizons, borrowing constraints, and general equilibrium. The results show that precautionary saving contributes modestly to aggregate saving, with the saving rate increasing by no more than three percentage points for moderate risk aversion and earnings variability. However, for high variability and persistence in earnings, the saving rate could increase by up to seven to fourteen percentage points. The model also highlights the importance of asset trading for consumption smoothing, with individuals able to reduce consumption variability by about half through optimal asset accumulation and decumulation. The model is consistent with observed income and wealth distributions, showing positive skewness and greater wealth inequality compared to income. The analysis also suggests that the presence of incomplete markets and liquidity constraints leads to lower interest rates and higher aggregate capital stock compared to complete markets. The paper concludes that the model provides valuable insights into the role of idiosyncratic risk and liquidity constraints in shaping aggregate saving and income distribution.This paper analyzes the impact of uninsured idiosyncratic risk and liquidity constraints on aggregate saving in a modified standard growth model. The model incorporates individual precautionary saving motives and borrowing constraints, leading to higher aggregate saving rates compared to complete markets. The key features of the model include endogenous heterogeneity, aggregation, infinite horizons, borrowing constraints, and general equilibrium. The results show that precautionary saving contributes modestly to aggregate saving, with the saving rate increasing by no more than three percentage points for moderate risk aversion and earnings variability. However, for high variability and persistence in earnings, the saving rate could increase by up to seven to fourteen percentage points. The model also highlights the importance of asset trading for consumption smoothing, with individuals able to reduce consumption variability by about half through optimal asset accumulation and decumulation. The model is consistent with observed income and wealth distributions, showing positive skewness and greater wealth inequality compared to income. The analysis also suggests that the presence of incomplete markets and liquidity constraints leads to lower interest rates and higher aggregate capital stock compared to complete markets. The paper concludes that the model provides valuable insights into the role of idiosyncratic risk and liquidity constraints in shaping aggregate saving and income distribution.