In The Last of Us, many human enemies wear armor to protect them from enemy gunfire. They cover the user's body with a bulletproof vest and their head with a helmet, making those who wear them tough to defeat. Some infected are covered in thick fungus that acts like armor; this is most easily seen on Bloaters. Given the player can only obtain armor in Factions MP, Joel and Ellie cannot use armor.
Some enemies that are encountered wear armor. Since they absorb most of the damage done from firearms, they require more gunshots in order to kill. However, damaged caused by melee attacks (including shivving and choking) bypasses this protection, as well as firing at the wearer's exposed limbs (as a shot to arms or legs will do the same amount of damage as a shot to the torso). Upgraded melee weapons, for example, kill targets in one hit, regardless of whether they have armor or not.
Certain weapons that inflict high amounts of damage, such as the Hunting Rifle with the armor piercing upgrade, have the power to penetrate armor.
Most of the infected are never armoured; the ones which do wear bulletproof vests do so for purely cosmetic purposes. Bloaters, however, have thick fungus that acts like armor, absorbing damage from gunfire. Unlike non-infected, they cannot be killed as easily by a melee weapon, due to their strength and thick armor, which absorbs much more damage than a bulletproof vest. This fungal armor is still highly vulnerable to fire damage from Flamethrowers and molotovs.
A armored vest and helmet. Breaks when it takes too much damage.
— In-game description.
In Factions MP, armor can be purchased, with the starting price at 450 part and increasing by 50 with each subsequent purchase. Costs are reduced if the player uses the Cheaper Armor One-Time Booster. Armor may be purchased as long as the buyer has enough parts and doesn't have a fully intact helmet and vest; purchasing armor always gives a fully intact vest and helmet, replacing the buyer's existing armor (if any). Until destroyed, armor carries on between lives.
Once purchased, armor consists of a vest and a helmet. Both decrease the amount of damage done to the player by 50% until they break. Both can break once they take a sustained amount of damage; they can also break independently of each other. While the vest is more likely to be useful as the body is a larger target than the head, the helmet protects the wearer from one-shot headshot downs from weapons such as the Hunting Rifle, El Diablo, and the Military Sniper. However, all these weapons completely destroy the helmet in just one shot, leaving the wearer vulnerable to follow-up shots. As in singleplayer, armor does not reduce damage taken by melee attacks and shivs but still protects players even when they are downed, making it tougher for someone to execute them with gunfire. Conversely, destroying a target's armor while they are downed is a fast and usually risk-free way to remove their armor so that they are no longer protected by it when they respawn.
Armor does not protect the wearer's legs and feet, making targeting the lower body a viable option against armor users. Although there are some character models that gain kneepads when they purchase armor, this is for appearances only; kneepads do nothing to protect users from damage, making it an ideal place to target when the opponent has armor equipped.
Helmets can be changed in character customization, as well as adding an emblem to their helmet for cosmetic value only; this does not change gameplay.