UFC Interim Title Explained: Why a Second Belt Exists
A UFC interim title is a second belt in one division, made when the champion cannot defend. How the Las Vegas promotion creates, unifies and removes them.
By CricketTaken EditorialPublished UFC & MMA25 min read
- First interim title fight
- UFC 43, June 2003
- First interim champion
- Randy Couture
- Rounds in an interim title fight
- 5
- Interim champions later stripped
- 3
Tom Aspinall had about two and a half weeks. The main event of UFC 295 at Madison Square Garden on November 11, 2023, was supposed to be Jon Jones defending the heavyweight title against Stipe Miocic. Jones was injured in training, the fight was off, and the UFC wanted a heavyweight title fight to keep on a card in New York. So it made one. Aspinall fought Sergei Pavlovich for a belt that had not existed a month earlier, knocked him out in 69 seconds, and left the building as a UFC champion in a division that already had one.
That is an interim title. It is a second championship in the same weight class, created by the UFC when the reigning champion cannot or will not defend, with a physical belt, a five-round fight sanctioned as a title bout by the state athletic commission, and an understanding that the two champions will eventually meet to unify. No rule says when one must be created. No rule says the unification fight must take place. The promotion decides both, case by case, which is why interim belts have been everything from an honest stopgap to a way of rescuing a Saturday night.
What a UFC interim title is, and what it is not
Three things make an interim title real. The fight for it is a championship fight in the eyes of the regulator, so it is scheduled for five rounds and not three; our guide to three-round and five-round fights explains why that distinction matters. Both fighters must weigh no more than the division limit, without the one-pound allowance commissions give in ordinary bouts. And the winner is handed a belt that looks the same as the one the regular champion owns.
What the interim champion does not get is the division. The regular champion is still the champion. On the UFC's own lists the titleholder remains at the top and the interim champion is placed directly beneath, at the head of the contenders, an arrangement described in our guide to the ranking lists and how they are compiled.
- 2003Year of the first interim title fight
- 26Interim reigns to date
- 4Successful interim title defenses
- 3Interim champions stripped
Counted by this page from the UFC's title histories through October 2026. A defense is counted only where the interim champion retained the belt.
The word is doing two jobs
"Interim" suggests a caretaker, someone holding an office until the real holder comes back. Sometimes that is accurate. Often it is not. Several interim champions were plainly the best active fighter in the division at the time they won, and the regular champion's claim rested on a fight a year or two old.
The word also carries a promise the UFC has not always kept: that the arrangement is temporary and will be resolved in the cage. Of the twenty-six interim reigns through October 2026, sixteen ended in a unification fight. The other ten ended some other way.
Nothing in the rulebook
Athletic commissions in the United States regulate bouts. They license the fighters, approve the matchup, assign the officials, run the weigh-in. They do not create championships and have no view on how many a promoter may have per division. The Unified Rules of Mixed Martial Arts define a foul and a round and a weight class; they do not define a champion.
So the interim title exists purely as a matter of the UFC's own practice. There is no published policy document. Everything that follows on this page is a description of what the promotion has done, which is the only authority there is.
When a UFC interim title gets created, and why no clock triggers it
Dominick Cruz won the UFC bantamweight title at the end of 2010, defended it twice in 2011, and then did not fight again until September 2014. Knee injuries, and later a groin injury, kept him out for nearly three years. The UFC waited about nine months after his last defense before creating an interim title, in July 2012, and kept Cruz as champion for another year and a half after that.
Ciryl Gane fought Derrick Lewis for an interim heavyweight title in August 2021. The regular champion, Francis Ngannou, had won the belt a little over four months earlier. He was not injured. He was not available on the date the promotion wanted for a show in Houston.
Those two cases are the range. Nine months in one, four in the other, and in neither did a rule decide it.
| Why the champion was absent | Example | What the UFC did |
|---|---|---|
| Injury with a return expected | Dominick Cruz, bantamweight, 2012 | Interim title, won by Renan Barao |
| Contract standoff | Randy Couture, heavyweight, 2008 | Interim title, won by Antonio Rodrigo Nogueira |
| Commission suspension | Khabib Nurmagomedov, lightweight, 2019 | Interim title, won by Dustin Poirier |
| Fighting in another division | Alexander Volkanovski, featherweight, 2023 | Interim title, won by Yair Rodriguez |
| Long inactivity | Conor McGregor, lightweight, 2017 | Interim title, won by Tony Ferguson |
| Unavailable for a chosen date | Francis Ngannou, heavyweight, 2021 | Interim title, won by Ciryl Gane |
The five circumstances
Injury is the classic one and the easiest to defend. A champion with a torn knee ligament may be out for a year, the division has contenders who deserve to fight for something, and an interim belt lets the weight class keep moving.
A contract dispute is the second. The very first interim title came from one, and so did the heavyweight version of 2008, when Randy Couture had resigned from the promotion while still champion.
Suspension is the third, and it is rarer than might be expected. When Khabib Nurmagomedov was suspended by the Nevada State Athletic Commission after the brawl that followed UFC 229, the promotion staged an interim lightweight title fight in April 2019. More often the UFC has simply stripped a suspended champion. A titleholder who fails a test under the promotion's anti-doping program has usually been removed, not covered for.
The fourth is the champion who goes after a second belt. Conor McGregor spent 2016 fighting at welterweight and then lightweight as the featherweight champion, and an interim featherweight title was made at UFC 200 in his absence. Alexander Volkanovski challenged for the lightweight title in February 2023, and an interim featherweight belt was contested on the very same card in Perth.
The fifth is the hardest to justify: a champion who is healthy and willing but not on the promotion's timetable.
Which divisions have had the most
Heavyweight leads by a distance, with nearly a third of all the interim belts ever made. The reasons are structural. Heavyweight champions have tended to be older and to fight less often, the division has been thin enough that one absence stalls everything, and it has had more than its share of contract arguments. The divisions and the pound limits that define them are covered separately.
The three ways an interim reign ends
An interim champion's story has three possible endings, and it is worth being exact about how often each has occurred.
- The belt is createdThe UFC announces an interim title fight because the champion is not defending. The winner receives a belt.
- Ending one, unificationThe champion returns and the two meet over five rounds. The winner is the undisputed champion and the interim title disappears.
- Ending two, promotionThe champion retires, vacates or is stripped. The UFC upgrades the interim champion to undisputed champion without a fight.
- Ending three, strippingThe interim champion cannot take the fight the promotion wants. The UFC removes the interim title and moves on.
The three outcomes that have actually occurred in the UFC. Which one happens is decided by results in the cage and by the promotion, not by any written rule.
The first is the one the word promises. The champion comes back, the two fight, and the division has a single titleholder again. Sixteen interim reigns ended this way. The interim champion won eight of those fights and lost eight, a split that says something about the quality of the fighters given these belts. They have not been caretakers.
The second is promotion. The regular champion never returns, or returns in another division, or is stripped, and the UFC announces that the interim champion is now the champion. Six times.
The third is the reverse. The interim champion is the one who becomes unavailable, and the promotion takes the belt back. Three times.
- Won the unification fight30.8%
- Lost the unification fight30.8%
- Promoted without a fight23.1%
- Stripped11.5%
- Lost the interim belt in a defense3.8%
Counted by this page through October 2026. The single reign in the last slice is Antonio Rodrigo Nogueira's in 2008, which ended when he lost the interim belt to another contender before any unification fight.
Show the numbers
| Item | Value |
|---|---|
| Won the unification fight | 8 |
| Lost the unification fight | 8 |
| Promoted without a fight | 6 |
| Stripped | 3 |
| Lost the interim belt in a defense | 1 |
One reign fits none of the three. Antonio Rodrigo Nogueira won the interim heavyweight title in February 2008 and lost it that December to Frank Mir, who took it into a unification fight of his own. An interim belt changing hands between contenders has happened exactly once.
The first one: Couture, Liddell and the interim heavyweight belts of the 2000s
Tito Ortiz was the UFC light heavyweight champion in the spring of 2003 and one of the promotion's biggest draws. He had not fought since the previous November. The obvious challenger was Chuck Liddell, a former training partner, and Ortiz was in a dispute with the company over money and showed no urgency about taking the fight.
The UFC's answer was to make a title without him. At UFC 43 in Las Vegas on June 6, 2003, Liddell fought for an interim light heavyweight championship against Randy Couture, a former heavyweight champion who was a few weeks short of his fortieth birthday and dropping down a division for the first time. Liddell was expected to win and was the intended beneficiary. Couture stopped him in the third round.
The device worked as designed, if not for the fighter it was designed for. Ortiz came back. At UFC 44 that September, Couture beat him over five rounds by decision to unify the belts. The whole episode took less than four months, and it gave the UFC a template: an absent champion could be pressured, and a division kept alive, by creating a second belt.
Four interim heavyweight champions in five years
The promotion used the template most at heavyweight.
Andrei Arlovski won the first interim heavyweight title in February 2005, while champion Frank Mir was recovering from injuries sustained in a road accident. Arlovski defended the interim belt once and was then promoted to full champion that August, when it became clear Mir was not close to returning.
The 2008 version was stranger. Randy Couture, back at heavyweight and champion again, had resigned from the UFC in late 2007. The promotion matched Antonio Rodrigo Nogueira and Tim Sylvia for an interim title in February 2008, and Nogueira won. Then Couture settled his dispute and came back, which left the division with a returning champion, an interim champion and a rising star in Brock Lesnar. The UFC arranged what amounted to a four-man bracket: Lesnar beat Couture for the regular title in November 2008, Mir beat Nogueira for the interim one in December, and Lesnar beat Mir at UFC 100 in July 2009 to unify.
Lesnar then fell ill, and the cycle repeated. Shane Carwin knocked out Mir for another interim title in March 2010. Lesnar returned that July and submitted Carwin in the second round after surviving a first round he nearly lost.
By 2010 four fighters had held an interim heavyweight belt in a little over five years. The idea had stopped being an emergency measure and become a normal part of how the UFC managed the division.
Every interim champion, and how each reign ended
The full list is short enough to print. It is complete through October 7, 2026, and it will lengthen.
| Year won | Division | Interim champion | Beat, and where | How the reign ended |
|---|---|---|---|---|
| 2003 | Light heavyweight | Randy Couture | Chuck Liddell, UFC 43 | Beat Tito Ortiz to unify |
| 2005 | Heavyweight | Andrei Arlovski | Tim Sylvia, UFC 51 | Promoted |
| 2007 | Welterweight | Georges St-Pierre | Matt Hughes, UFC 79 | Beat Matt Serra to unify |
| 2008 | Heavyweight | Antonio Rodrigo Nogueira | Tim Sylvia, UFC 81 | Lost the interim belt to Frank Mir |
| 2008 | Heavyweight | Frank Mir | Nogueira, UFC 92 | Lost to Brock Lesnar |
| 2010 | Heavyweight | Shane Carwin | Frank Mir, UFC 111 | Lost to Brock Lesnar |
| 2012 | Welterweight | Carlos Condit | Nick Diaz, UFC 143 | Lost to Georges St-Pierre |
| 2012 | Bantamweight | Renan Barao | Urijah Faber, UFC 149 | Promoted |
| 2014 | Heavyweight | Fabricio Werdum | Mark Hunt, UFC 180 | Beat Cain Velasquez to unify |
| 2015 | Featherweight | Conor McGregor | Chad Mendes, UFC 189 | Beat Jose Aldo to unify |
| 2016 | Light heavyweight | Jon Jones | Ovince Saint Preux, UFC 197 | Stripped |
| 2016 | Featherweight | Jose Aldo | Frankie Edgar, UFC 200 | Promoted |
| 2016 | Featherweight | Max Holloway | Anthony Pettis, UFC 206 | Beat Jose Aldo to unify |
| 2017 | Middleweight | Robert Whittaker | Yoel Romero, UFC 213 | Promoted |
| 2017 | Lightweight | Tony Ferguson | Kevin Lee, UFC 216 | Stripped |
| 2018 | Welterweight | Colby Covington | Rafael dos Anjos, UFC 225 | Stripped |
| 2019 | Lightweight | Dustin Poirier | Max Holloway, UFC 236 | Lost to Khabib Nurmagomedov |
| 2019 | Middleweight | Israel Adesanya | Kelvin Gastelum, UFC 236 | Beat Robert Whittaker to unify |
| 2020 | Lightweight | Justin Gaethje | Tony Ferguson, UFC 249 | Lost to Khabib Nurmagomedov |
| 2021 | Heavyweight | Ciryl Gane | Derrick Lewis, UFC 265 | Lost to Francis Ngannou |
| 2021 | Bantamweight | Petr Yan | Cory Sandhagen, UFC 267 | Lost to Aljamain Sterling |
| 2022 | Flyweight | Brandon Moreno | Kai Kara-France, UFC 277 | Beat Deiveson Figueiredo to unify |
| 2023 | Featherweight | Yair Rodriguez | Josh Emmett, UFC 284 | Lost to Alexander Volkanovski |
| 2023 | Heavyweight | Tom Aspinall | Sergei Pavlovich, UFC 295 | Promoted |
| 2026 | Lightweight | Justin Gaethje | Paddy Pimblett, UFC 324 | Beat Ilia Topuria to unify |
| 2026 | Heavyweight | Ciryl Gane | Alex Pereira, UFC Freedom 250 | Promoted |
Read down the right-hand column and the pattern of the last decade shows. From 2003 to 2014 there were nine interim titles in twelve years. From 2015 to 2023 there were fifteen in nine. The belt became more common as the UFC's schedule grew and its need for championship main events grew with it.
Two names appear twice. Justin Gaethje lost a unification fight in 2020 and won one in 2026, on a card staged on the South Lawn of the White House. Ciryl Gane lost his in 2022 and, four years later, never had to fight a second.
Promotion without a unification fight
Renan Barao held the interim bantamweight title for almost eighteen months. He won it in July 2012, defended it twice in 2013, and was scheduled to meet Dominick Cruz at UFC 169 in February 2014 to settle the matter at last. A few weeks before the fight Cruz was injured again. The UFC stripped him and announced that Barao was now the bantamweight champion. He defended that title on the same card on which he had been due to try to win it.
Barao was not the first to be upgraded, since Arlovski had been promoted in 2005, but his case set the modern pattern. Jose Aldo was promoted in November 2016, when Conor McGregor gave up the featherweight belt. Robert Whittaker was promoted in December 2017, when Georges St-Pierre vacated the middleweight title a month after winning it.
Then Aspinall. He won the interim heavyweight title in November 2023, defended it in July 2024, and waited. Jon Jones fought once in that period, against Miocic in November 2024, and not against the interim champion. In June 2025 the UFC announced that Jones had retired and that Aspinall was the undisputed heavyweight champion. He had held the interim belt for more than nineteen months without getting the unification fight.
The sequel came quickly. Aspinall's first defense as full champion, against Gane in Abu Dhabi in October 2025, ended in the first round as a no contest after an accidental eye poke, a kind of result our guide to fights ruled a no contest explains. With Aspinall unable to compete, the promotion made another interim heavyweight title, which Gane won against Alex Pereira in June 2026. Aspinall vacated that September. Gane was promoted.
When did the reign begin
Promotion creates an accounting puzzle. Was Aspinall the heavyweight champion from November 2023, when he won a UFC belt, or from June 2025, when the word "interim" was removed?
The UFC's title histories date an undisputed reign from the day of the promotion, not from the day the interim belt was won. On that reckoning Barao's reign as champion began in January 2014 and Aspinall's in June 2025. The interim period is recorded as a separate, earlier reign.
That is tidy and slightly unfair. A fighter who wins an interim title and is later promoted has, in practice, been the division's leading active fighter the whole time. Barao beat three contenders with a belt on the line before anyone called him the champion. The official record gives him credit for that period under a lesser heading, and a fan counting days as champion will get a smaller number than the fighter's career deserves.
There is a harder question underneath. A promoted champion never beat the person he replaced. The lineal idea that sustains every combat sports title, that you become the champion by beating the champion, is broken by a promotion. Nothing can be done about it when a champion retires. It is worth noticing, though, how often the UFC has ended up in that position after choosing not to make the unification fight when it could have.
Defending an interim belt, and why it almost never happens
An interim title is supposed to have one fight in its future. Once it exists, the next bout for its holder should be against the regular champion. A defense means the plan has failed: the champion is still not back, the interim champion has been idle long enough that he needs to fight, and the promotion has to put a second contender in front of him.
Only three fighters have retained an interim belt. Andrei Arlovski did it once, against Justin Eilers in June 2005. Renan Barao did it twice in 2013, against Michael McDonald in London and Eddie Wineland in Toronto, while Cruz's absence stretched past two years. And Tom Aspinall did it at UFC 304 in Manchester, England, on July 27, 2024, knocking out Curtis Blaydes in one minute flat.
The Aspinall defense was the first of its kind in more than a decade, and it was controversial for a specific reason. Jones was by then on course to return, against Miocic. The UFC had a champion with a fight in view and an active interim champion in the same division, and chose to book them in separate fights against other people. An interim title is meant to cover an absence, and by the end of 2024 there was no absence left to cover.
The risk an interim champion takes by fighting
For the fighter, defending is a gamble with poor terms. Win, and he is where he was, still waiting. Lose, and the belt and the guaranteed unification fight both go to someone else, which is what happened to Nogueira in 2008.
Most interim champions therefore prefer to wait, and the promotion's patience with waiting varies. Carlos Condit won the interim welterweight title in February 2012 and sat out nine months until Georges St-Pierre was ready. The UFC let him. Others have been pushed toward a fight or, as the next section shows, relieved of the belt for not being available on a particular night.
Interim belts that led nowhere: Ferguson, Covington and Jones
Tony Ferguson won the interim lightweight title in October 2017 by submitting Kevin Lee in Las Vegas. The regular champion, Conor McGregor, had not fought in the division since winning the belt eleven months earlier. A unification fight was never booked. The UFC instead matched Ferguson with Khabib Nurmagomedov for UFC 223 in Brooklyn in April 2018 and declared that the winner would be the undisputed champion, stripping McGregor in the process.
About a week before that fight, Ferguson injured his knee in a fall. The UFC stripped him too. Nurmagomedov beat a late replacement and became champion. Ferguson, who had won a UFC title fight six months earlier and lost nothing since, was a contender again. He never fought for the undisputed title.
Colby Covington's case was quicker. He won the interim welterweight title in Chicago in June 2018, with champion Tyron Woodley recovering from surgery. When Woodley was ready that September, Covington was not, having had surgery of his own. The promotion booked Woodley against another challenger and Covington's interim title was removed. It had lasted three months. He did eventually fight for the welterweight championship, at the end of 2019, as an ordinary challenger.
Jon Jones is the third. He won the interim light heavyweight title in April 2016, was pulled from the unification fight at UFC 200 days before it over a potential anti-doping violation, and was stripped later that year after being suspended.
The power behind all three
The Jones case is defensible on any view; a suspended fighter cannot hold a title in trust. The other two are what the interim title looks like from the fighter's side. Ferguson and Covington each won a five-round championship fight. Each was unavailable for a single date. Each lost the belt without losing a bout.
No appeal exists. The interim title is the UFC's creation, the athletic commission has no jurisdiction over who holds it, and no independent body ranks or sanctions it. The promotion can make the belt on two weeks' notice and unmake it with a press release. That is the fact a reader should hold onto when asking whether an interim champion is a "real" champion. The championship is real. The security of it is not.
The belt as an event rescue
Pay-per-view cards are sold on title fights. When a championship main event collapses close to the date, the UFC has a commercial problem, and the interim title is the fastest fix available.
UFC 189 in July 2015 is the model. Jose Aldo, the featherweight champion, withdrew injured less than two weeks before he was due to fight Conor McGregor in Las Vegas, in what had been promoted for months as the biggest fight of the year. Chad Mendes stepped in, the bout was made for an interim title, and McGregor won in the second round. The card kept its championship billing. When McGregor and Aldo did meet that December, the fight was bigger for the wait.
UFC 295 followed a similar script eight years later, as the opening of this page describes, though there the interim fight was the co-main event beneath another title bout. So did UFC 249 in May 2020, when Khabib Nurmagomedov could not travel during the first weeks of the pandemic and Justin Gaethje replaced him against Ferguson for an interim belt.
UFC 206 and the limits of the device
The clearest example of the title being stretched came in Toronto in December 2016. The scheduled main event, a light heavyweight title fight, fell through. The UFC elevated a featherweight bout between Max Holloway and Anthony Pettis and attached an interim featherweight title to it.
The difficulty was that featherweight had a champion who was fit and available. Jose Aldo had been promoted from interim to full champion only two weeks earlier. An interim title was being created in a division whose regular champion had just been installed, for no reason except that a card needed a belt on the poster. Then Pettis missed weight, which made him ineligible to win it under the rules covered in our guide to what happens when a fighter misses weight. A title fight in which only one man could win the title headlined the show.
Holloway won, and beat Aldo the following June, so the sporting outcome was respectable. The process was not. Critics who call the interim belt a scheduling device more than a sporting honor have UFC 206 as their best evidence, and UFC 236 in April 2019, which carried two interim title fights on one card, as their second.
It is fair to say both things at once. Interim title fights have regularly been excellent, between the two best available fighters in a division, and several were made for reasons that had more to do with the calendar than the champion. The difference between a card with a title fight and a card without one is laid out in our guide to numbered events and Fight Nights.
How the record books treat an interim title, and what "undisputed" is doing
Start with the lists. The UFC's title histories record interim champions as champions, in sequence with the regular titleholders and marked as interim. An interim reign that ended in a lost unification fight still appears. Shane Carwin and Yair Rodriguez are in the record as former UFC champions of a kind, and both are commonly introduced as "former interim champion," a phrase that concedes the asterisk.
Counting gets less consistent from there. A win in an interim title fight is generally included when a fighter's total of title-fight victories is quoted on a broadcast. A streak of consecutive title defenses is generally counted from the regular belt only, so a fight won as interim champion is a title-fight win without being a defense of the division's championship. Promoted champions carry two entries. The promotion publishes no rules for its own record keeping, and the totals quoted for a given fighter can differ by one or two depending on who compiled them. The same looseness applies to honors such as the UFC Hall of Fame, where an interim reign is part of a fighter's case without any fixed weight.
The borrowed word
"Undisputed" is a term from boxing, where it has a precise meaning: one fighter holding the belts of all the major sanctioning bodies in a division at once. It describes the end of a dispute among organizations.
The UFC has one organization and one belt per division, so in the ordinary case there is nothing to dispute and the word is decoration. Every UFC champion is announced as the undisputed champion, whether or not an interim belt exists. The term only does real work in the weeks when a division has two titleholders, and then it means simply "the one whose belt is not interim."
Which leaves the unification fight as the one occasion on which the UFC's vocabulary and boxing's line up. Two recognized champions meet, and one leaves with everything.
Interim against vacant: why the UFC sometimes strips the champion instead
When a champion is out, the promotion has two tools. It can leave the champion in place and add an interim belt. Or it can take the title away and match two contenders for the vacant championship. The choice turns mostly on one question, whether the champion is expected back in the division, and partly on whether the promotion wants him back.
| Champion's situation | What the UFC did | Example |
|---|---|---|
| Injured, return expected | Created an interim title | Cain Velasquez, heavyweight, 2014 |
| Retired | Vacated the title; vacant-title fight | Khabib Nurmagomedov, lightweight, 2021 |
| Left the promotion | Stripped; vacant-title fight | Francis Ngannou, heavyweight, 2023 |
| Moved to another division | Vacated; vacant-title fight | Islam Makhachev, lightweight, 2025 |
| Suspended | Stripped; vacant-title fight | Jon Jones, light heavyweight, 2015 |
| Retired with an interim champion in place | Promoted the interim champion | Jon Jones, heavyweight, 2025 |
A vacant-title fight produces an undisputed champion immediately. Nobody waits for anyone, no unification fight hangs over the division, and the winner's reign is clean in the record. From a sporting point of view it is the better outcome whenever the old champion is truly gone.
The interim route keeps a door open. It tells the absent champion the belt is still his and tells the public a bigger fight is coming. That is valuable when the absent champion is a star. It is also why the choice so often tracks the fame of the fighter involved: a popular champion with an uncertain future tends to get an interim belt made beneath him, and a less marketable one in the same position tends to be stripped.
Khabib Nurmagomedov's exit shows how long the UFC will hold a door open. He announced his retirement in the cage in October 2020. The promotion kept him listed as lightweight champion until the following March, hoping he would reconsider, and created no interim title in the meantime. Only then was the belt declared vacant. The thinking behind decisions of this kind is the subject of our explainer on who picks the fights.
The contrast with boxing's interim, regular and super champions
Boxing had the interim title first, and boxing shows what happens when the idea is left to multiply.
Each of the sport's major sanctioning bodies can name an interim champion in any division when its titleholder is inactive. Some go further. One body has for years recognized a "super" champion above a "regular" champion in the same weight class, and others have created designations for champions in recess or champions elevated above the mandatory system. With four bodies doing some version of this across seventeen weight classes, a single division can contain half a dozen men with a claim to be called world champion. The site's guide to the WBC, WBA, IBF and WBO sets out who does what.
The UFC's version is simpler by construction. One promoter. One belt per division. At most one interim belt alongside it, and never two.
Boxing's interim titles do have one feature the UFC's lack: rules. A sanctioning body's regulations typically say when an interim title may be created, how long a champion may be inactive, and when the interim champion must be given the fight or elevated. Those rules are bent constantly, but they exist and a fighter's team can cite them. In the UFC the interim champion's position rests on the promotion's intentions and nothing else.
So the comparison cuts both ways. A UFC interim title is rarer and easier to follow than its boxing equivalent, and in most cases has been won against stronger opposition. It is also less secure, because the body that awards it answers to no rulebook when it takes it away. More on both sports sits in the site's combat sports section.