Method for manufacturing a modular lifting surface in a family of aircraft from a standard lifting surface of dimensions previously defined, wherein the standard lifting surface comprises a standard central support structure, the standard central support structure having an upper and a lower standard skin (12, 13) and at least a first standard spar, wherein the modular lifting surface comprises a central support structure, the central support structure having an upper and a lower skin and at least a first spar, the method comprising the following steps: a) providing the upper and lower skin for the modular lifting surface, wherein the upper and lower skin correspond to the upper and lower standard skin, respectively, so that according to a cross section (A-A, B-B, C-C) of the modular lifting surface, the upper and lower skin have a chord length which corresponds to a standard chord length D of the upper and lower standard skin, wherein the cross section (A-A, B-B, C-C) of the modular lifting surface is in a transversal plane parallel to a vertical plane and to a longitudinal axis of the aircraft, b) dimensioning and providing the at least first spar from the at least first standard spar by modifying or keeping the dimension of a standard first height H ' 1 of said at least first standard spar c) assembling the at least first spar to both the upper and lower skin, respectively, for obtaining the central support structure, so that the at least first spar is located between the upper and lower skin (2, 3) defining a first end (1.1) of the central support structure, d) dimensioning and providing a leading edge and a trailing edge according to the central support structure e) assembling the leading edge to the central support structure where the at least first spar is assembled to the upper and lower skin, and assembling the trailing edge to the central support structure at a second end (1.2) of the central support structure, the second end (1.2) being opposite to the first end (1.1) where the at least first spar is located, f) obtaining the modular lifting surface having a size that is different from the size of the standard lifting surface. a) providing the upper and lower skin for the modular lifting surface, wherein the upper and lower skin correspond to the upper and lower standard skin, respectively, so that according to a cross section (A-A, B-B, C-C) of the modular lifting surface, the upper and lower skin have a chord length which corresponds to a standard chord length D of the upper and lower standard skin, wherein the cross section (A-A, B-B, C-C) of the modular lifting surface is in a transversal plane parallel to a vertical plane and to a longitudinal axis of the aircraft, b) dimensioning and providing the at least first spar from the at least first standard spar by modifying or keeping the dimension of a standard first height H ' 1 of said at least first standard spar c) assembling the at least first spar to both the upper and lower skin, respectively, for obtaining the central support structure, so that the at least first spar is located between the upper and lower skin (2, 3) defining a first end (1.1) of the central support structure, d) dimensioning and providing a leading edge and a trailing edge according to the central support structure e) assembling the leading edge to the central support structure where the at least first spar is assembled to the upper and lower skin, and assembling the trailing edge to the central support structure at a second end (1.2) of the central support structure, the second end (1.2) being opposite to the first end (1.1) where the at least first spar is located, f) obtaining the modular lifting surface having a size that is different from the size of the standard lifting surface.