On February 16, 2010, Slater was announced as one of eight wrestlers to compete on the first season of the WWE NXT show, with Christian as his storyline mentor. On the inaugural episode of NXT, Slater won his debut match as he and Christian defeated Carlito and Michael Tarver in a tag team match. Two weeks later, Slater defeated Carlito, becoming the first NXT rookie to beat a WWE pro in a singles match. On the March 30 episode of NXT he came fourth out of eight rookies in the first Pros' Poll. On the April 6 episode, Slater won a keg-carrying contest against all other rookies. This resulted in him being in the main event that night, a match against Kane, that he lost. In an upset victory on April 20, Slater defeated Chris Jericho in the main event of NXT. However, Slater remained at fourth in the second Pros Poll, revealed on May 11. He was eliminated from NXT on May 25, coming in last in the Pros' Poll.
On the June 7 episode of Raw, Slater and the other season one NXT rookies turned heel by interfering in the main event match between John Cena and CM Punk, attacking both competitors, the announcing team and Justin Roberts, the ring announcer, before dismantling the ring area and surrounding equipment. On the June 14 episode of Raw the rookies (excluding Daniel Bryan, who had been released) attacked General Manager Bret Hart, when he refused to give them contracts. At the Fatal 4-Way pay-per-view, the seven rookies interfered in the WWE Championship match, as a result costing Cena the championship. The following week on Raw, Vince McMahon fired Hart and announced the hiring of a new General Manager, who had signed the seven season one NXT rookies to contracts. The following week, the group was named The Nexus. On the July 12 episode of Raw, The Nexus competed in their first match together, without Darren Young, a six–on–one handicap match against John Cena, which they won when Justin Gabriel pinned Cena. The Nexus continued to feud with Cena and the Raw roster, resulting in a seven-on-seven elimination tag team match at SummerSlam. Cena's team won when Cena eliminated Gabriel and then Wade Barrett to win the match.
In October 2010, Cena was forced to join The Nexus as a result of losing to Barrett at Hell in a Cell, and at the following pay-per-view, Cena and David Otunga won the WWE Tag Team Championship. On the October 25 episode of Raw, Barrett made a tag team match, with Justin Gabriel and Slater facing Otunga and Cena for the championship. Gabriel and Slater won when Barrett ordered Otunga to allow Slater to pin him, becoming the new Tag Team Champions. Gabriel and Slater held the championship for nearly two months, before losing it to Santino Marella and Vladimir Kozlov in a four-way elimination match also involving The Usos and Mark Henry and Yoshi Tatsu on the December 6 episode of Raw. Gabriel and Slater received a rematch for the championship at the TLC: Tables, Ladders & Chairs pay-per-view on December 19, but lost by disqualification when Nexus member Michael McGillicutty interfered.
On the January 10, 2011, episode of Raw Gabriel and Slater refused to take part in new Nexus leader CM Punk's initiation and walked away from the group.
The following day, at the tapings of the January 14 eisode of SmackDown, Gabriel and Slater helped their former leader Wade Barrett and Ezekiel Jackson attack Big Show. The following week, Gabriel, Slater, Barrett, and Jackson announced they had formed the Corre, and later that night Gabriel defeated World Heavyweight Champion Edge in a non-title match, following interference from the other members of The Corre. After winning a non-title match against the champions Kozlov and Marella on the February 4 episode of SmackDown, Gabriel and Slater received a match for the WWE Tag Team Championship two weeks later, but lost via disqualification when the other members of The Corre interfered. They received a rematch at the Elimination Chamber pay-per-view on February 20 and defeated Marella and Kozlov to win the WWE Tag Team Championship for the second time.
The following night on Raw, Gabriel and Slater lost the championship to John Cena and The Miz, but won the championship back minutes later after Barrett invoked The Corre's rematch clause, and The Miz turned on Cena. During this time, The Corre had continued to feud with The Big Show, and at WrestleMania XXVII in April the team of The Big Show, Kane, Santino Marella, and Kofi Kingston defeated The Corre. At the April 19 taping of SmackDown, the duo of Gabriel and Slater lost the Tag Team Championship to the team of Kane and The Big Show. In a backstage segment following the match, Gabriel was attacked by Slater, who thought Gabriel blamed him for their loss. On the May 6 episode of SmackDown, Gabriel, Barrett, and Slater attacked Jackson, removing him from the group. On the June 10th edition of SmackDown, when Barrett walked out on Gabriel and Slater in a 6-man tag team match against Jackson and The Usos, Gabriel and Slater told Barrett later backstage that The Corre was over.
They would start a feud with The Usos. On the June 17 edition of SmackDown, Gabriel and Slater, with new music, were defeated by The Usos, later defeating them in a rematch on the June 24 edition. The next day he together with Gabriel were announced for the SmackDown Money in the Bank match in Chicago, Illinois. They were again defeated by The Usos on the July 8 edition, having a visible disagreement and argument in the ring following the match.
On the July 15 edition of SmackDown, Slater started a feud with Gabriel when he verbally berated him saying that Gabriel was holding him down. That same night, Slater lost to Gabriel after receiving a 450° splash. At Money in the Bank on July 17, he and Gabriel participated in the SmackDown Money in the Bank ladder match, which was won by Daniel Bryan.
On October 17, 2011, WWE suspended Heath Slater due to a Wellness Violation for 30 days.
Slater, winless since July 28, ended 2011 on an 18-match TV/PPV losing streak, topping Edge's 17-match winning streak to achieve WWE's longest streak of 2011. On the January 6 edition of Smackdown, Heath Slater lost to Hornswoggle in an Over the Rope challenge and attacked him before his former tag team partner, Justin Gabriel saved Hornswoggle and hit the 450 splash to Slater. Slater broke his 22 match losing streak by defeating Trent Barreta on NXT Redemption on January 25, 2012. He continued his winning streak two weeks later on WWE NXT by defeating Derrick Bateman. On March 29, 2012 on WWE Superstars, Slater ended his losing streak by defeating Alex Riley after losing to the likes of Justin Gabriel and Brodus Clay. Slater continued his winning streak when he once again defeated Alex Riley. On the June 11th edition of Raw, Slater was defeated by the returning Vader. On the June 18th edition of Raw one week later, Slater made an appearance to abuse Wendi Richter and Cyndi Lauper, only to be interrupted by Roddy Piper, and was finally hit by Lauper with a glass CD box. He defeated Doink the Clown on the July 2 edition of Raw. After the match Diamond Dallas Page came to the ring and shook Slater's hand, appearing to congratulate him, before hitting Slater with the Diamond Cutter. On the July 9 edition of Raw, after losing a match, Bob Backlund came to the ring and after a few moments of playing up to the crowd and suffering a cheap shot from Slater, Backlund applied the crossface chicken wing to make Slater tap out. On July 12th at an NXT taping at Full Sail University, Scotty 2 Hotty defeated Slater using the Worm. On the July 16th episode of Raw, Slater lost to Rikishi. On the July 20th episode of Smackdown, Slater lost to Road Warrior Animal. During the 1000th episode of Raw on July 23 he lost to Lita, with help from the APA and all of the legends that Slater had lost to in the preceding weeks on Raw. On the July 30th edition of Raw, Slater challenged any active WWE Superstar to a match. Randy Orton returned and defeated him.
On the September 23, 2012 episode of SmackDown, Drew McIntyre and Jinder Mahal interfered in Slater's match against Brodus Clay by attacking Clay. The trio would later settle for the name of the Three Man Band, or 3MB for short. From October 2012, 3MB would rack up many wins against Team CoBro (Santino Marella and Zack Ryder) and the Usos, all of them due to illegal interference. At the TLC pay per view, 3MB's winning streak came to an end at the hands of The Miz, Alberto Del Rio and the Brooklyn Brawler. The next night at the Slammy Awards Raw show, 3MB would lose again to The Miz, Alberto Del Rio, and Tommy Dreamer. On the 20th Anniversary of Raw on January 14, 2013, 3MB won an Over the Top Challenge against Sheamus. Slater and McIntyre represented 3MB in the NXT Tag Team Championship Tournament, but were defeated in the first round by Adrian Neville and Oliver Grey. He participated in the Royal Rumble coming from number 10 but was eliminated by John Cena. On the April 12th edition of SmackDown, Slater, along with the rest of 3MB, attempted to ambush Triple H as he was addressing Brock Lesnar; The Shield then came out and attacked them. On the April 15th episode of Raw, 3MB called out The Shield but instead it was Brock Lesnar who came out and attacked the three of them, delivering the F-5 on Slater twice on the barricade. On the 29th April, 2013 edition of RAW, 3MB attacked The Shield, but The Shield quickly turned the tables on them. Team Hell No came to the ring, seemingly to aid 3MB, but The Shield escaped and Team Hell No attacked 3MB instead. On the May 22 edition of Main Event, Slater was abducted by the monstrous Ryback who entered the arena out of the back of an ambulance before throwing Slater inside and leaving. On the June 14 edition of WWE Superstars he defeated Zack Ryder with help from 3MB. On Smackdown Slater defeated The Great Khali.
On the November 11 edition of Raw in Manchester, 3MB came out as the "Union Jacks" and lost to the team of Los Matadores and Santino Marella. On the November 13 edition of WWE Main Event, Slater and McIntyre would defeat The Prime Time Players. On the November 15 edition of SmackDown, The Union Jacks were defeated by R-Truth and The Prime Time Players. On November 18, 3MB wrestled as "The Rhinestone Cowboys" to fit in the special Raw Country episode. They lost to R-Truth and the debuting Xavier Woods. Similarly, this trend of name changes continued to amount the group losses as they also lost to The Prime Time Players on SmackDown, as The Fabulous 3Birds, which was a play on legendary tag team, The Fabulous Freebirds. On the November 29 episode of Smackdown, they were billed as The Plymouth Rockers, a play on The Rockers tag team, even coming out to the Rockers' theme music, and faced Los Matadores, along with their mascot, El Torito in a losing effort. Shortly after that match, Slater took time off from WWE to deal with personal issues. He returned on the January 6, 2014 episode of Raw, which saw 3MB defeated by Rikishi and Too Cool. On April 4, 2014, Slater broke his losing streak, picking up the win against Kofi Kingston on WWE Superstars. At WrestleMania XXX, all three members entered the Andre the Giant Memorial Battle Royal and eliminated both The Great Khali and Xavier Woods as a unit, before all three were eliminated by Mark Henry. After WrestleMania, 3MB entered a feud with Los Matadores, which saw Hornswoggle ally himself with the trio so as to feud with El Torito. 3MB won their first match since December 2012 after Slater and McIntyre beat Los Matadores on the April 28 edition of Raw.
On June 12, both Jinder Mahal and Drew McIntyre were released from their WWE contracts, thus disbanding 3MB.
On the June 16th, 2014 episode of Raw, Heath Slater stood up to Rusev and Lana by responding to their anti-America promos, potentially turning him face in the process. However, he was quickly defeated by Rusev. On the June 26 episode of Superstars, Slater remained a heel where he faced Adam Rose in a losing effort. On the July 11 episode of SmackDown, Slater teamed up with Titus O'Neil to face The Usos, in which Jimmy and Jey won the match. At Battleground, Slater competed in a battle royal for the vacant Intercontinental Championship; Slater did not win the match, but managed to eliminate Cesaro in upset fashion and received the biggest ovation from the crowd in his career; he was then quickly eliminated by Sheamus. On the July 21 episode of Raw, Slater confronted Flo Rida about their previous confrontation at WrestleMania 28. This resulted in Flo Rida once again pushing Slater to the ground. Slater then began to regularly team up with Titus O'Neil. On the July 29 episode of Main Event, Slater and O'Neil became known as "Slater Gator" and picked up their first win over Tyson Kidd and Zack Ryder. On the August 1st episode of Superstars, Titus and Slater defeated Sin Cara and Zack Ryder. On the August 4th episode of Raw, Slater picked up an upset victory over Seth Rollins in a "Beat The Clock Challenge" match, after being put into the match by The Authority to replace Rob Van Dam. During the Raw Fallout, Slater and Titus O'Neil celebrated Slater's win. On the August 5 episode of WWE Main Event, Slater Gator defeated Goldust and Stardust. On the August 11th edition of Raw, Heath Slater picked up yet another upset victory, defeating Dolph Ziggler by countout. On the August 19 episode of WWE Main Event, Slater Gator defeated Los Matadores. Slater's brief winning streak was ended when Slater Gator were defeated by Los Matadores on the August 25 episode of Raw. Slater Gator then began a feud with Adam Rose and his bunny, who had attacked Slater on many occasions.
In his return to RAW on November 17, 2014, he returned as a face, in Uncle Sam attire and became the next victim against Rusev. The following Sunday, at Survivor Series, Slater remained a heel by teaming up with Titus O'Neil, losing to Adam Rose and The Bunny. After a short hiatus, Slater returned to action in a dark match against Luke Harper on February 3, 2015. On the February 12 edition of SmackDown, Slater-Gator competed in a tag team turmoil match, where they were quickly defeated by the team of Daniel Bryan and Roman Reigns. This would be the final time Slater-Gator would team up.
On the February 16 episode of Raw, Titus O'Neil made a face turn and reformed The Prime Time Players with Darren Young, effectively ending the team of Slater-Gator. At WrestleMania 31, Slater competed in the 30-man Andre the Giant Memorial Battle Royal which was won by Big Show. After primarily wrestling on Superstars, Slater returned to the scenes on the April 20 edition of Raw when he was at catering, only to get RKO'ed through the table by Randy Orton. On the May 29 episode of Superstars, Slater picked up a victory against Adam Rose. Throughout the rest of 2015, Slater would appear mostly on Superstars and Main Event losing to the likes of Fandango, Neville, R-Truth, and Zack Ryder.
On the January 4, 2016 Raw, Slater debuted a new stable of himself, Adam Rose, Bo Dallas, and Curtis Axel, calling themselves "social outcasts". Slater went on to defeat Dolph Ziggler after interference from his stablemates. On the January 11 Raw, Slater seemingly turned face for the first time in his career (along with his fellow stablemates) by helping Ryback fend off the Wyatt Family. However, on the following SmackDown, the Outcasts were once again playing heels when they defeated the team of Jack Swagger, Goldust, Zack Ryder, and Damien Sandow. On the January 18 episode of Raw he suffered a crushing defeat by the Big Show. The following night on an episode of Main Event, Slater and Curtis Axel defeated The Dudley Boyz in a tag team match. On the February 15, 2016 edition of Raw, Slater defeated Zack Ryder with the help of The Social Outcasts. On the February 25, 2016 episode of SmackDown, Slater suffered a loss against R-Truth after Goldust distracted him. On the March 17, 2016 episode of SmackDown, The Social Outcasts announced they would be participants in the 3rd annual André the Giant Memorial Battle Royal at WrestleMania 32, in which they were all unsuccessful. In May, The Social Outcasts began filming The Marine 5: Battleground, taking them out of action.
The Social Outcasts returned on the June 27 episode of Raw, confronting Enzo Amore and Big Cass. The following week on Raw, The Social Outcasts faced Enzo Amore and Big Cass in a losing effort.
While his fellow Social Outcast members got drafted by the end of the 2016 WWE Draft, Slater was the only active superstar not selected by either show. Slater appeared on the July 26 episode of SmackDown Live, cutting a promo addressing the issue, only to receive a Gore from a returning Rhyno shortly after. The week after on Raw, Slater made an appearance where he and the returning Jinder Mahal demanded contracts. Raw General Manager Mick Foley informed the pair that they must compete in a match for a Raw contract, in which Mahal came out victorious. On the August 9 episode of SmackDown Live, Slater lost against Rhyno in a match where if Slater won, he earned a SmackDown Live contract. On the August 15 edition of Raw, Slater interrupted Brock Lesnar and Paul Heyman to demand they show him respect, which caused Lesnar to beat down Slater when he refused to leave the ring. The following night on SmackDown Live, Slater faced off against Randy Orton, with Slater being offered a contract if he won; Orton was disqualified after refusing to stop punching Slater, resulting in Slater earning a contract offer, which was taken away by Shane after a dazed Slater mistook him for Stephanie and Bryan for Foley.
On the August 23 episode of SmackDown, Slater interrupted the introduction of the new WWE SmackDown Tag Team Championship. Daniel Bryan offered Slater a SmackDown contract if he could find a partner and win the tag team title tournament. After struggling to find a partner, former opponent Rhyno approached Slater and agreed to be his partner. Slater and Rhyno defeated the Headbangers (Mosh and Thrasher) in the first round and The Hype Bros (Zack Ryder and Mojo Rawley) in the semi finals to advance to the final match at Backlash. At the pay-per-view, Slater and Rhyno defeated The Usos to become the inaugural SmackDown Tag Team Champions, with Slater also winning a contract in storyline, in the process. On the 12 September edition of SmackDown, Slater and Rhyno defeated The Ascension to successfully retain the titles in their first defense, right after Slater signed his contract. On October 9 at No Mercy, Slater and Rhyno successfully defended the titles against The Usos. The following Tuesday on Smackdown, Slater and Rhyno came to the aid of Dolph Ziggler after he was attacked by The Miz and The Spirit Squad. The following week on SmackDown, Ziggler, Slater and Rhyno where defeated by The Miz and The Spirit Squad in a six-man tag team match. On the October 25 episode of SmackDown, Slater and Rhyno would retain their titles against The Spirit Squad. At Survivor Series, Slater and Rhyno were the team captains for Team SmackDown in the 10–on–10 Survivor Series Tag Team Elimination match, where they were defeated by Team Raw. At TLC (2016), Slater and Rhyno's tag team championship reign came to an end at 84 days after they were defeated by Randy Orton and Bray Wyatt.