Under some appropriate conditions, we prove the existence and uniqueness of periodic solutions to partial functional differential equations with infinite delay of the form $\dot{u}=A(t)u+g(t,u_t)$ on a Banach space $X$ where $A(t)$ is 1-periodic, and the nonlinear term $g(t,\varphi )$ is 1-periodic with respect to $t$ for each fixed $\varphi$ in fading memory phase spaces, and is $\phi (t)$-Lipschitz for $\phi$ belonging to an admissible function space. We then apply the attained results to study the existence, uniqueness, and conditional stability of periodic solutions to the above equation in the case that the family $(A(t){)}_{t\ge \hspace{0.17em}0}$ generates an evolution family having an exponential dichotomy. We also prove the existence of a local stable manifold near the periodic solution in that case.