Abstract: Testing method for subscriber line testing (TS, TL) in a program-controlled communications system or switching equipment (EWSD), whereby a first or a second test execution program module (CT, LT), a test address data program module (TA) and a test decision program module (UC) initiates and implements testing procedures. These are read out of a test data program module (CD) by version-associated query sequences in the sense of a decision tree (E) for the identification of test limit values. The test limit values that are needed for a line test can be prescribed by the operator.