't Hooft loop is an important conceptual tool in gauge theories in four dimensions. In particular, it is useful for determining the possible phases of the theory. However, due to the singularity at the source it is very hard to perform calculations with the 't Hooft loop. We present a way to deal with this singularity which lead to a finite result in supersymmetric theories. This result is in agreement with a certain prediction for a strongly coupled Wilson line.