Trifluoroperacetic acid can be easily prepared by an Organic Syntheses process of treating trifluoroacetic anhydride with a concentrated (90%) aqueous solution of hydrogen peroxide:
:trifluoroacetic anhydride|   +   hydrogen peroxide|   →      +   trifluoroacetic acid|
As the anhydride will form trifluoroacetic acid in contact with water, an excess of the anhydride also serves to remove the solvent from the peroxide reactant:
:   +   water|   →   2 
A more dilute hydrogen peroxide solution (30%) can be used to form trifluoroperacetic acid for some reactions from trifluoroacetic acid.
In order to avoid the danger of handling pure or highly concentrated solutions of hydrogen peroxide, hydrogen peroxide – urea can be used to give the peracid. This method involves no water, so it gives a completely anhydrous peracid, which is an advantage when the presence of water leads to side reactions during certain oxidation reactions.
: + hydrogen peroxide - urea| →  +  + urea|
In cases where a pH buffering agent is needed for a synthesis and where the presence of water is tolerated, another approach has been developed.  Reacting trifluoroacetic anhydride with sodium percarbonate, , yields trifluoroperacetic acid and sodium carbonate, obviating the need for an additional buffer.
:3  + 4 sodium percarbonate| → 6  + 4 sodium carbonate| + 3 
Trifluoroperacetic acid can also be generated in situ, allowing it to react promptly with the target substrate rather than pre-synthesizing a batch of the reagent for later use.