Methods, apparatus, systems and articles of manufacture to determine whether a smart device is in-tab are disclosed. An example apparatus includes a labelled data generator to identify a first smart television that corresponds to a first panelist by comparing first data from the first smart television to second data from the first panelist; and generate training data by labelling the first smart television as in-tab or out-of-tab based on the second data from the first panelist; and a model trainer to train a model using the training data, the model trainer to train the model to determine a tab status for a second smart television.