Methods and apparatus to charge accumulators are described. An example system to charge an accumulator apparatus includes a piston disposed within a housing to define a first chamber adjacent a first side of the piston and a second chamber adjacent a second side of the piston. A fill probe having a body and a passageway between a first end of the fill probe and a second end of the fill probe removably couples to the piston to fluidly couple to the passageway of the fill probe to the second chamber of the housing when the accumulator is in a charging condition. A valve is fluidly coupled to the piston to enable fluid flow to the second chamber of the housing via the piston when the fill probe is coupled to the piston.