Multipayer is class-based, with four classes: Assault, Engineer, Medic, and Recon. Each class has a variety of unique weapons and pieces of equipment, and serves a specific role in combat. There are also some weapons that can be used by any class, such as pistols and shotguns. Each class gains experience and levels up separately.
New items are unlocked by earning experience points, which are gained for performing actions conducive to the goals of the player's team, such as eliminating enemy players, healing teammates, or capturing or defending points of interest. These points also count towards a total of 50 ranks. Bonuses to the base number of points can be awarded under certain circumstances (such as achieving a headshot in the process of eliminating an enemy player).
The multiplayer features 15 vehicles, including new additions, such as the UH-60 Black Hawk, a quad bike, a four-man patrol boat, a personal watercraft, a ZU-23 mounted on a BMD-3 armored personnel carrier, and a UAV helicopter (a Northrop Grumman MQ-8 Fire Scout) controlled via remote computer terminals. The Mi-24 attack helicopter, dating back to Battlefield 2, has now been replaced by the more capable Mi-28, while the original is reintroduced as a transport helicopter.
The currently available maps are set in various environments such as South America and Alaska near the borders of Russia.[10], similar to those seen in the singleplayer.
Players can also use party chat for each game mode.[11] A dog tag system as seen in Battlefield 2142 and Battlefield: Bad Company returns, awarding players with their opponents' dog tags when they defeat them with a knife attack.[12] It uses the PunkBuster anti-cheat program, to protect the game from cheaters in online multiplayer matches.

Bad Company 2 features a story-driven single player campaign. For most of the narrative, the player takes control of Preston Marlowe, one of the members of Bad Company. The exception to this is the first mission set prior to the rest of the campaign. Each mission is divided into a series of objectives, often interspersed with cutscenes which simulate the style of films.
Aside from infantry combat, the campaign contains several missions in which the player controls a vehicle, or mans a weapon turret while a teammate controls the vehicle.
While the other members of Bad Company will engage in combat, the game relies upon the player to complete the objectives and kill most of the enemies. The player's allies can never die.
Each weapon in the campaign is considered a collectible - the first time the player picks up that type of weapon, a "Collectible Unlocked" message appears. There are also sensor stations throughout the campaign the player can find and destroy - this is also recorded in the campaign stats. "Supply Drop" crates are scattered throughout the missions - the player can exchange weapons and replenish ammo at these drops. The Supply Drop crates will remember any weapon the player picks up and this weapon will be available for the rest of the campaign.

As a first-person shooter, Bad Company 2 places the player in direct control of an infantry soldier in warfare. While first-person shooter combat is the primary focus of the game, controllable vehicles also play a significant role in gameplay. On foot, players are given access to a variety of real-world small arms such as assault rifles and machine guns. Vehicles, also based on real-life equivalents, include ATVs, APCs, tanks, and helicopters.
While on foot, players can jump, crouch, and sprint. They can carry one primary weapon and a pistol in multiplayer, or two primary weapons in single player, as well as grenades and other equipment. Players can fire "from the hip", but zooming in and using the weapon's iron sights, reflex sight, or scope (depending on the weapon) will provide much better accuracy when shooting.
Bad Company 2 heavily emphasizes destructible environments. Large sections of most buildings can be destroyed by explosives; some walls and fences break down under barrages of bullets. The game's physics engine realistically simulates the destruction.
The game utilizes a "regenerating health" system, rather than giving players health points as older games in the Battlefield series have done. To accommodate this in multiplayer, the Medic equipment now accelerates health regeneration rather than directly restoring the player's health. If a player is wounded, he or she must take cover and avoid being wounded, and health will slowly be recovered. A heavily wounded player will see dirt and blood around the edges of the screen. Along with Battlefield Vietnam, Bad Company 2 is one of only two games in the Battlefield series to show blood[9] without third-party modification.