A holster for a handgun comprising a holster body made of a substantially rigid and non-pliable material and configured for securely receiving a handgun therein. The holster body comprising a holster cavity configured for securely accommodating and partially embracing portions of the handgun, and a retention arrangement comprising a left-side trigger guard member and a right-side trigger guard member facing one another and configured for snug fitting within the handgun's trigger guard. At least one of the trigger guard members is a hinged trigger guard member, pivotally secured to the holster body.