A recently established crossover equation of state for pure chain fluids is extended to chain-fluid mixtures. Far from the critical region, where density fluctuations are small, it reduces to the classic equation of state. Near or at the critical point, the crossover equation of state incorporates contributions form long-wavelength density fluctuations. Using segment - segment parameters for pure components and one cross parameter k(12) for every binary pair as obtained from vapor -liquid equilibrium data remote from the critical region, this crossover equation of state glues vapor-liquid equilibria in good agreement with experiment for binary asymmetric mixtures of n-alkanes far from near to, and at the critical point.