In one aspect, a method for noise reduction in parallel magnetic resonance (MR) imaging using a plurality of radio frequency (RF) coils is provided. The method comprises performing a first MR scan of a target to obtain first MR data, performing a second MR scan of the target to obtain second MR data, the second MR data obtained from operating the plurality of coils substantially in parallel, computing a noise estimate associated with the second MR data based at least in part on the first and second MR data, and obtaining a noise-reduced image based at least in part on the second MR data and the noise estimate.