A plate heat exchanger, comprising: ∘ a plurality of heat exchanger plates which are stacked and permanently connected to form a plate package that defines first and second fluid paths for a first medium and a second medium, respectively, separated by said heat exchanger plates, said plate package defining a surrounding external wall that extends in an axial direction between first and second axial ends, ∘ an end plate (21; 24) permanently connected to one of the first and second axial ends so as to provide an end surface that extends between first and second longitudinal ends in a lateral plane which is orthogonal to the axial direction, and ∘ two mounting plates permanently connected to a respective surface portion of the end surface at the first longitudinal end and the second longitudinal end, respectively, such that the mounting plates are spaced from each other in a longitudinal direction on the end surface, wherein the respective mounting plate comprises opposing flat engagement surfaces (12, 13) and a peripheral edge that forms a perimeter of the mounting plate, ∘ wherein the respective mounting plate is arranged with one of its engagement surfaces (12, 13) permanently connected to the end surface, wherein the peripheral edge partially extends beyond the outer periphery of the end surface, so as to define a mounting flange, and partially extends across the end surface in contact with the same, ∘ wherein the respective mounting plate comprises intersection regions which are located where the peripheral edge intersects with the perimeter of the surrounding external wall as seen in a normal direction to the end surface, characterized in that predefined intersection regions of said intersection regions have a decreasing thickness towards the peripheral edge. ∘ a plurality of heat exchanger plates which are stacked and permanently connected to form a plate package that defines first and second fluid paths for a first medium and a second medium, respectively, separated by said heat exchanger plates, said plate package defining a surrounding external wall that extends in an axial direction between first and second axial ends, ∘ an end plate (21; 24) permanently connected to one of the first and second axial ends so as to provide an end surface that extends between first and second longitudinal ends in a lateral plane which is orthogonal to the axial direction, and ∘ two mounting plates permanently connected to a respective surface portion of the end surface at the first longitudinal end and the second longitudinal end, respectively, such that the mounting plates are spaced from each other in a longitudinal direction on the end surface, wherein the respective mounting plate comprises opposing flat engagement surfaces (12, 13) and a peripheral edge that forms a perimeter of the mounting plate, ∘ wherein the respective mounting plate is arranged with one of its engagement surfaces (12, 13) permanently connected to the end surface, wherein the peripheral edge partially extends beyond the outer periphery of the end surface, so as to define a mounting flange, and partially extends across the end surface in contact with the same, ∘ wherein the respective mounting plate comprises intersection regions which are located where the peripheral edge intersects with the perimeter of the surrounding external wall as seen in a normal direction to the end surface, ∘ wherein the respective mounting plate is arranged with one of its engagement surfaces (12, 13) permanently connected to the end surface, wherein the peripheral edge partially extends beyond the outer periphery of the end surface, so as to define a mounting flange, and partially extends across the end surface in contact with the same, ∘ wherein the respective mounting plate comprises intersection regions which are located where the peripheral edge intersects with the perimeter of the surrounding external wall as seen in a normal direction to the end surface,