Experimental study on the airside performance of compact slit fin-and-tube heat exchangers was carried out. Test results indicated the airside performance for compact slit fin geometry is relatively independent of the number of tube row and fin pitch. The results are quite different from previous studies concerning the slit fin geometry. This may be attributable to a smaller slit breadth of this study. Test results of the present slit fin were compared with louver fin and plain fin using various comparison methods. In all cases, the relevant airside performance of the interrupted surfaces (including louver and slit) is superior to that of plain fin surface. However, it should be pointed out that the associated superiority may decrease with decreasing fin pitch and Reynolds number. An updated correlation of the airside performance for the slit fin geometry describing 56 test samples is proposed. The mean deviation of the proposed heat transfer correlation is 7.26% and is 7.18% for frictional correlation.