A method for producing a coil holder for a magneto-inductive flowmeter by means of injection molding, wherein the coil holder has two coil cores molded in a plastic casting, each with a first longitudinal axis, wherein the method comprises the following steps: Providing and positioning a mold with a cast volume and the two coil cores in a first process step, wherein each coil core has two end faces and a lateral face, wherein the end faces of each coil core intersect the respective first longitudinal axis, preferably orthogonally, wherein the lateral face has a central section (33.3) and two outer sections (33.4) enclosing the central section, wherein the cast volume fully encloses the central sections in one core section each, wherein the outer sections and the end faces are preferably outside of the cast volume; Filling the cast volume with a plastic in a second process step; Curing the plastic or letting it cure in a third process step; Removing the mold from the plastic casting in a fourth process step, characterized in that the cast volume is continuous, wherein the first longitudinal axes of the coil cores are identical, wherein each coil core has an internal end face (33.2), said internal end face being directed toward the other coil core in each case, wherein the internal end faces span an intermediate area, said intermediate area being at least partially free from plastic casting, in particular in a central section, wherein the plastic casting has an indentation in a first plane containing the first longitudinal axes, said indentation encompassing the space and defining an open side of the coil holder, wherein the plastic casting is not continuous in a second plane containing the first longitudinal axes and positioned perpendicular to the first plane. wherein the coil holder has two coil cores molded in a plastic casting, each with a first longitudinal axis, wherein the method comprises the following steps: Providing and positioning a mold with a cast volume and the two coil cores in a first process step, wherein each coil core has two end faces and a lateral face, wherein the end faces of each coil core intersect the respective first longitudinal axis, preferably orthogonally, wherein the lateral face has a central section (33.3) and two outer sections (33.4) enclosing the central section, wherein the cast volume fully encloses the central sections in one core section each, wherein the outer sections and the end faces are preferably outside of the cast volume; Filling the cast volume with a plastic in a second process step; Curing the plastic or letting it cure in a third process step; Removing the mold from the plastic casting in a fourth process step, characterized in that the cast volume is continuous, wherein the first longitudinal axes of the coil cores are identical, wherein each coil core has an internal end face (33.2), said internal end face being directed toward the other coil core in each case, wherein the internal end faces span an intermediate area, said intermediate area being at least partially free from plastic casting, in particular in a central section, wherein the plastic casting has an indentation in a first plane containing the first longitudinal axes, said indentation encompassing the space and defining an open side of the coil holder, wherein the plastic casting is not continuous in a second plane containing the first longitudinal axes and positioned perpendicular to the first plane. Providing and positioning a mold with a cast volume and the two coil cores in a first process step, wherein each coil core has two end faces and a lateral face, wherein the end faces of each coil core intersect the respective first longitudinal axis, preferably orthogonally, wherein the lateral face has a central section (33.3) and two outer sections (33.4) enclosing the central section, wherein the cast volume fully encloses the central sections in one core section each, wherein the outer sections and the end faces are preferably outside of the cast volume; Filling the cast volume with a plastic in a second process step; Curing the plastic or letting it cure in a third process step; Removing the mold from the plastic casting in a fourth process step, characterized in that the cast volume is continuous, wherein the first longitudinal axes of the coil cores are identical, wherein each coil core has an internal end face (33.2), said internal end face being directed toward the other coil core in each case, wherein the internal end faces span an intermediate area, said intermediate area being at least partially free from plastic casting, in particular in a central section, wherein the plastic casting has an indentation in a first plane containing the first longitudinal axes, said indentation encompassing the space and defining an open side of the coil holder, wherein the plastic casting is not continuous in a second plane containing the first longitudinal axes and positioned perpendicular to the first plane.