Sam gets a new sleek coat when he and Dean travel to Chicago. There are two different version of this jacket, one lighter one (grey) and one darker one (black). They're hard to tell apart in certain lighting configurations, so I've listed them in the same category. I'll differentiate them where I can. The darker version appears kind of greeny-black indoors, but outdoors looks more blue. It’s got minimal style elements, except for a seamless pocket on the right breast. It does up with large dark buttons and has large lower flap pockets.
Brand: Quiksilver (Ace Jacket)
Sam wears this coat for the entire episode of Bloodlines (9x20) (black)
In Stairway to Heaven (9x22), Sam wears this coat when he and Cas travel to find Josiah. He wears it until the end of the episode.
In Do You Believe in Miracles (9x23), Sam wears this coat for the entire episode, only taking it off before he put Dean in his room and grieves.
In Reichenbach (10x02), Sam wears this coat after he exits his hotel and Crowley finds him to give him Dean’s location in exchange for the First Blade. He keeps it on until the end of the episode. (grey)
Sam wears this coat for the entire episode of Ask Jeeves (10x06) (black)
In There’s No Place Like Home (10x11), Sam puts on this coat when he and Dean are leaving the Bunker to go track down Charlie. He wears suits to interview the first two witnesses, but otherwise wears this coat whenever he is not inside the Bunker for the rest of the episode. He also doesn’t wear it when he, Charlie and Dean are sitting in bars. (The coat looks a little lighter than usual in this episode, though that may be attributed to the lighting.) (grey)
In Halt & Catch Fire (10x13), Sam wears this coat anytime he is not in a suit. (black)
In Inside Man (10x17), Sam wears this coat when he goes to meet Cas, and keeps it on until he gets home from his secret mission. (grey)
In The Werther Project (10x19), Sam wears this coat when he goes to St. Louis to investigate the Werther Box. He takes it off briefly when he decides to try to open the box with his blood. He wears it until the end of the episode. (black)
In Brother’s Keeper (10x23), Sam wears this coat when he goes to see Rowena with Cas, and then again after he’s been to the crime-scene in Nebraska and starts looking for the Impala at motels (successfully finding Dean’s motel room). He keeps it on for the rest of the episode. (grey)
In Out of the Darkness, into the Fire (11x01), Sam continues to wear this coat for the entire episode. (grey)
In Form and Void (11x02), Sam continues to wear this coat, but takes it off while working inside the hospital. (grey)
In Just My Imagination (11x08), Sam wears this jacket when they go to investigate Sparkle’s death with Sully. He takes it off briefly in order to wear a disguise to enter the house and view Sparkle’s body, but other than that, he wears it for the rest of the episode.
In Into the Mystic (11x11), Sam wears this coat to salt and burn a corpse, and then again when he and Dean guard Mildred and wait for the banshee to strike.
In The Chitters (11x19), Sam wears this coat when he meets up with Dean at the bar and is introduced to Cesar and Jesse. He keeps it on for the rest of the episode.
In The One You’ve Been Waiting For (12x05), Sam wears this coat for the whole episode, only taking it off when they are inside the diner (both times.)
In Rock Never Dies (12x07), Sam wears this coat on the drive to LA and when they meet up with Castiel and Crowley. He then changes into a “rock musician” disguise.
In Family Feud (12x13), Sam wears this coat in the car on the way to the case, before changing into a suit for a while. He then wears it again when they pick up Gavin from the bus depot. He keeps it on until they go back to the Bunker to send Gavin back in time.
In Somewhere Between Heaven and Hell (12x15), Sam wears this coat when they go into the woods with Crowley to Hunt the Hell Hound. He wears it until the end of the episode. (light)
In The British Invasion (12x17), Sam wears this coat at the beginning of the episode when he and Dean arrive at the Bunker to find Mick waiting for them, and then subsequently any time that he is outside, and also when we see them return to the Bunker after the hunt. (dark)
In Wayward Sisters (13x10), Sam wears this jacket at the end of the episode when he says goodbye to Jody. (dark version)
In The Thing (13x17), Sam wears this jacket while they’re investigating, and dealing with the consequences of their actions at, the Men of Letter’s Chapter House in Portsmouth. He wears it until the end of the episode.