We address the problem of reasoning about interleavings in safety verification of concurrent programs. In the literature, there are two prominent techniques for pruning the search space. First, there is \emph{state-based} interpolation where a collection of formulas can be generalized by taking into account the property to be verified. Second, there are \emph{trace-based} methods, collectively known as ``Partial Order Reduction (\por{})'', which operate by weakening the concept of a trace by abstracting the total order of its transitions into a partial order. Our main contribution is a framework that \emph{synergistically} combines state interpolation with \por{} so that the sum is more than its parts.