We used identification at threshold to systematically measure binding costs in two visual modalities. We presented a conjunction of two features as a signal stimulus and concurrently measured detection and identification performance as a function of three threshold variables: duration, contrast and coherence. Discrepancies between detection and identification sensitivity functions demonstrated a consistent processing cost to visual feature binding. Our findings suggest that feature binding is indeed a genuine problem for the brain to solve. This simple paradigm can transfer across arbitrary feature combinations and is therefore suitable to use in experiments addressing mechanisms of sensory integration.