Cleaning
The major use for Trisodium Phosphate is in cleaning agents.

TSP is an excellent agent for cleaning everything from laundry to concrete driveways.

TSP is commonly used after cleaning with mineral spirits in order to remove hydrocarbon residues. Although it is still the active ingredient in some toilet bowl cleaning tablets, TSP is generally not good for cleaning bathrooms, because it can corrode metal and can damage grout

Use as a Painting Enhancement

TSP is still in common use for the cleaning, degreasing and deglossing of walls prior to painting. TSP breaks the gloss of oil based paints and opens the pores of latex based paint providing a surface better suited for the adhesion of the subsequent layer of paint.