A method for preparing tetrabromobenzoate ester from a tetrabromophthalic anhydride including the steps of reacting the tetrabromophthalic anhydride with a catalyst and an alcohol at a temperature that favors partial esterification over complete esterification of the tetrabromophthalic anhydride to form a tetrabromophthalate half-ester reaction mixture; and feeding the half-ester reaction mixture to at least one reactor having and maintaining a temperature that favors decarboxylation over esterification to produce a tetrabromobenzoate ester-containing product. The temperature favoring partial esterification of the tetrabromophthalic anhydride is between about 70.degree. C. and 130.degree. C. The temperature favoring decarboxylation over esterification is between about 190.degree. C. and 205.degree. C. The tetrabromobenzoate ester-containing product comprises at least about 85% tetrabromobenzoate ester. The at least one reactor may include two or more reactors connected to one another in series.