We streamlined the five-step SEDEX (sedimentary extraction) procedure for characterizing sedimentary phosphorus to a four-step procedure. We combined extraction of adsorbed and oxide-associated pools into a single step, retaining steps for authigenic, detrital, and organic P. In addition, we used automated spectrophotometric flow injection analysis (FIA) to determine P concentrations, rather than traditional spectrophotometric techniques. We decreased our total extraction and analytical time from 12 d for 24 replicate samples to 5 d without sacrificing our geochemical objectives, detection limits, or analytical reproducibility.