Process for the coproduction of acetic anhydride and acetic acid in the liquid phase under substantially anhydrous conditions which comprises the steps of: continuously combining in a first carbonylation reactor components comprising: (i) at least one feedstock compound selected from methyl acetate, dimethyl ether or a combination thereof; and (ii) a first carbon monoxide stream, to produce a first liquid reaction composition in a liquid phase, wherein: the components are combined in the presence of a carbonylation catalyst, the components are combined under conditions effective to convert at least some of the feedstock compound to acetic anhydride, and the first liquid reaction composition comprises: (i) at least some unreacted feedstock compound, (ii) dissolved carbon monoxide and (iii) acetic anhydride product; continuously removing at least part of the first liquid reaction composition from the first carbonylation reactor and contacting the at least part of the first liquid reaction composition with methanol in an esterification zone to form a second liquid reaction composition in a liquid phase under conditions effective to cause at least some of the acetic anhydride from the first reaction composition and at least some of the methanol to react to produce methyl acetate and acetic acid in the second liquid reaction composition; continuously feeding the second liquid reaction composition to a second carbonylation reactor along with additional carbon monoxide to produce a third liquid reaction composition in a liquid phase, wherein: the second liquid reaction composition and a second carbon monoxide stream are combined under conditions effective to cause at least some unreacted feedstock compound, methyl acetate from, or both to be converted to acetic anhydride, and the third reaction composition comprises (i) unreacted feedstock compound, methyl acetate from or both, (ii) acetic acid, and (iii) acetic anhydride product, and continuously removing the third liquid reaction composition from the second carbonylation reactor. continuously combining in a first carbonylation reactor components comprising: (i) at least one feedstock compound selected from methyl acetate, dimethyl ether or a combination thereof; and (ii) a first carbon monoxide stream, to produce a first liquid reaction composition in a liquid phase, wherein: the components are combined in the presence of a carbonylation catalyst, the components are combined under conditions effective to convert at least some of the feedstock compound to acetic anhydride, and the first liquid reaction composition comprises: (i) at least some unreacted feedstock compound, (ii) dissolved carbon monoxide and (iii) acetic anhydride product; the components are combined in the presence of a carbonylation catalyst, the components are combined under conditions effective to convert at least some of the feedstock compound to acetic anhydride, and the first liquid reaction composition comprises: (i) at least some unreacted feedstock compound, (ii) dissolved carbon monoxide and (iii) acetic anhydride product; continuously removing at least part of the first liquid reaction composition from the first carbonylation reactor and contacting the at least part of the first liquid reaction composition with methanol in an esterification zone to form a second liquid reaction composition in a liquid phase under conditions effective to cause at least some of the acetic anhydride from the first reaction composition and at least some of the methanol to react to produce methyl acetate and acetic acid in the second liquid reaction composition; continuously feeding the second liquid reaction composition to a second carbonylation reactor along with additional carbon monoxide to produce a third liquid reaction composition in a liquid phase, wherein: the second liquid reaction composition and a second carbon monoxide stream are combined under conditions effective to cause at least some unreacted feedstock compound, methyl acetate from, or both to be converted to acetic anhydride, and the third reaction composition comprises (i) unreacted feedstock compound, methyl acetate from or both, (ii) acetic acid, and (iii) acetic anhydride product, and the second liquid reaction composition and a second carbon monoxide stream are combined under conditions effective to cause at least some unreacted feedstock compound, methyl acetate from, or both to be converted to acetic anhydride, and the third reaction composition comprises (i) unreacted feedstock compound, methyl acetate from or both, (ii) acetic acid, and (iii) acetic anhydride product, and continuously removing the third liquid reaction composition from the second carbonylation reactor.