Several inference types serving distinct purposes are established in the literature on reading comprehension. Despite this highlighting that inference is a non-unitary construct, reading tests tend to treat it as a single ability. Consequently, different tests can assess different inferential abilities. Professionals, knowing what is implicitly assessed in an assessment tool, can make informed decisions on test selection and take a critical approach to interpreting test outcomes.This article examines the inferential abilities assessed by the "New Salford Sentence Reading Test" and the "Diagnostic Reading Analysis." Both are aimed at practitioners working with children of primary and secondary school age. Each takes inference to be a unitary construct. Qualitative analysis of the inferential questions in the tests revealed that they assess different forms of inference. The "New Salford Sentence Reading Test" predominantly assesses inferences requiring background knowledge. In contrast, the "Diagnostic Reading Analysis" requires inferences relying on textual evidence to a greater extent. The article concludes that it is reasonable to assert that the "Diagnostic Reading Analysis" is preferable to the "New Salford Sentence Reading Test" on the basis of test fairness and the consistency in sampling inferences types.