In this paper, we introduce a new multi-state PDFT method called linearized PDFT (L-PDFT) in which we express the Hamiltonian ( ĤL-PDFT ) in second quantization as an operator that is a functional of the density and pair density. We construct ĤL-PDFT by expanding the MC-PDFT energy functional in a power series of ρ and Π variables about their state-averaged values within the model space and truncate this series at first order, such that for any state |I⟩, ⟨I| ĤL-PDFT |I⟩ is a linear approximation to its MC-PDFT energy.