Non-local terms are generally present in any quantum effective action in presence of light fields, and there are indications that they could arise also in the IR regime of General Relativity. I will discuss the possibility that such terms could affect the late time cosmological evolution thus providing an explanation of the dark energy phenomenon. I will show under which conditions a phenomenological model inspired by the above considerations is compatible with cosmological observations (CMB, Baryon Acoustic Oscillations, Supernovae data, structure formation, local measurements of the Hubble parameter) to a degree of accuracy which is statistically equivalent to that of the consensus reference model based on LambdaCDM.