Experimental measurements of heat transfer coefficient have been made for forced-convection condensation of oil-refrigerant (R-12) mixtures inside a horizontal tube. From these measurements, a correlation is developed to predict heat transfer coefficient for a wide range of parameters. The range of parameters is as follows: mass flux from 7 × 104to 7 × 105lbm/hr·ft2(3.4 × 105to 3.4 × 106kg/hr·m2), heat flux from 1100 to 22,000 Btu/hr·ft2(3.5 × 103to 6.9 × 104W/m2), vapor qualities from 0.2 to 0.8, condensing pressures from 70 to 135 psia (0.48 to 0.93 MPa absolute), and oil fractions of 0, 2, and 5%. Comparison of the proposed correlation with experimental data shows that 82% of the data are within ±20%.