Between Ciudad Real and Daimiel, the A-43 runs parallel to the road shared by the N-420 and N-430 routes, while between Daimiel and Manzanares (where it also connects with the Autovía A-4) it runs parallel to the N-430 alone. Between Manzanares and Atalaya del Cañavate, it runs parallel to the N-310.
In the future, the A-43 will be extended westwards from Ciudad Real to the Autovía A-5 near Mérida, in Extremadura, again running parallel to the N-430.