The notion of endomorphism congruence considered in this paper has a close connection with the notion of result. To say most generally, results are fractions such that their numerators are elements of a certain linear space while their denominators are injective endomorphisms of that space. Generally, division by an endomorphism is led out of range of elements. In connection with it we obtain the regular and singular results. Using the endomorphism congruence properties we can decide about regularity of certain results on the basis of the others confirming, if they are regular or singular. The adequate examples in the Bittner operational calculus are given.