The concept of the PT symmetry has been intensively investigated in optics on the basis of the paraxial wave equation governing the propagation of light in guiding structures, as this equation is similar to the Schrödinger equation in quantummechanical models, where the PT symmetry was first introduced. In this work, we go beyond the paraxial approximation to demonstrate, solving the full set of the Maxwell's equations for the light propagation in deeply subwavelength waveguides and periodic lattices with balanced gain and loss (in a numerical form), that the PT symmetry may remain unbroken in this setting. Moreover, the PT symmetry in subwavelength guiding structures may be restored after being initially broken with the increase of gain and loss. Critical gain/loss levels, at which the breakup and subsequent restoration of the PT symmetry occur, strongly depend on the underlying guiding structure.