The Transfer Line Balancing Problem (TLBP) deals with the optimization of design solutions for serial machining lines. Such lines consist of a sequence of transfer machines. At every machine, the operations are performed by blocks. The blocks are processed sequentially and the operations within each block are executed simultaneously by the same multi-spindle head. The line design objective is to group the operations into blocks and assign the blocks to machines minimizing the total amount of the required equipment (spindle heads and machines). The challenge is to minimize the line cost and time for decision making. The best exact and heuristic methods for TLBP are compared in a computational experiment. Experimental results are presented. These results are useful for determining the best optimization method for each type of the design problem.