The impact of tower staggering on the magnetic field distributions under parallel power lines is thoroughly investigated. The staggering techniques are classified into two types; artificial staggering applied at parallel lines with the same span length and natural staggering resulted from parallel lines with different span lengths. The lateral magnetic field profiles of typical parallel lines for both types of staggering are developed and analyzed taken into consideration the effects of staggering distance, one line disconnection, line spacing, phase arrangement, current direction and line loading.