This protocol describes a technique to recover viruses from natural waters using iron- based flocculation and large-pore-size filtration, followed by resuspension of virus- containing precipitates in a pH 6.5 buffer. This Fe-based virus flocculation, filtration and resuspension method (FFR) is efficient (> 90% recovery), reliable, inexpensive and adaptable to many aspects of marine viral ecology and genomics research. Recovered viruses are amenable to gene sequencing, and a variable proportion of phages, depending upon the phage, retain their infectivity when recovered if using oxalic acid in the resuspension buffer. Particles lose infectivity if resuspended with ascorbic acid in the buffer.