->'''Robin:''' Let's make a pact. If we both turn 40 and we're both single...\\
'''Ted:''' Robin Scherbatsky - will you be my backup wife?\\
'''Robin:''' A girl always dreams of hearing those words. Yes, yes, a million times, yes!
-->--''HowIMetYourMother''

Two unlucky-in-love PlatonicLifePartners or FriendsWithBenefits, not wanting to grow old alone, agree to marry each other if they're [[OldMaid still single after a certain age]]. Can be played either sincerely or for laughs, but either way it's likely to be a FriendshipMoment.

If the pair have been going through a WillTheyOrWontThey plot, it's a handy way to bring it to [[BetterAsFriends an amicable close]] without irreversibly deciding that They Don't.

Sometimes this trope is seen from the other side; an OldFlame (usually one who's [[NewOldFlame never been mentioned before]]) shows up to remind a character that they once made such a pact together, and they're here to collect on the deal. HilarityEnsues, especially if they've aged into an AbhorrentAdmirer and the other character [[OldFlameFizzle doesn't want them any more]]. If one party has forgotten about it entirely or never took it seriously, the other may say "ItMeantSomethingToMe".

A DefiedTrope of ChristmasCake / OldMaid. See also HonorableMarriageProposal.

Closely related to ChildhoodMarriagePromise, which is a similar agreement made by kids too young to really understand what marriage is. See also ArrangedMarriage.

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!!Examples:

[[foldercontrol]]

[[folder: Fan Works ]]

* An interesting variant is used in the ''WesternAnimation/MyLittlePonyFriendshipIsMagic'' fanfic "[[http://www.fimfiction.net/story/106068/1/relax/intimacy Relax]]". The protagonist and the prostitute he regularly sees make plans to marry assuming that he survives the war and she hasn't been either moved away, fallen for somebody else, or been bought as a personal SexSlave. It's quite heartwarming.
* Brought up but ultimately averted in ''Fanfic/RomanceAndTheFateOfEquestria''. Twilight, still a BrokenBird from her previous relationship, isn't ready for another and wants herself and Donut Joe to be FriendsWithBenefits. As the hope of a relationship with her was the only thing keeping him in Equestria, he decides to go through with his plan to take a five-year journey with the travelling Bazaar, leading Twilight to propose this trope if they're both still single when the Bazaar returns to Equestria. Through further discussion, they realize that this trope would be too heartbreaking if only one of them was single, so Twilight instead suggests that they [[IWillWaitForYou remain faithful to one another]] and [[LongDistanceRelationship stay in touch]] for the next five years, and get together at the end no matter what.

[[/folder]]

[[folder: Film ]]

* ''MyBestFriendsWedding'' where this trope, and the main character's attempt to wreck her best friend's relationship so that she doesn't end up being the UnluckyChildhoodFriend form the central plot. [[spoiler: She fails, nearly wrecking her ''friendship'' with the guy in the process.]]

[[/folder]]

[[folder: Literature ]]

* In ''Literature/{{Overenskommelser}}'' by Creator/SimonaAhrnstedt, Seth has one of these with his NewOldFlame Lily Tremaine. They're friends rather than lovers, but still decide to get engaged. But in the end, [[spoiler: they break it up when Seth is reunited with Beatrice (the story's female protagonist) and Lily finds true love with Alexandre (with whom Beatrice had a similar relationship).]]

[[/folder]]

[[folder: Live Action TV ]]

* In ''Series/HappyEndings'' Penny is mentioned as having a marriage pact with ButtMonkey Shershow, who ends up getting married in the first season finale, prompting Penny to fake being engaged to not feel bad about her own singledom.
* Ted and Robin make one in ''Series/HowIMetYourMother'', which pretty much (but not entirely) marks the end of their WillTheyOrWontThey arc. Apparently the term "Ted & Robin pact" has entered the vernacular. [[spoiler:This is discarded as of season 7.]]
* Discussed on ''Series/{{Friends}}''; Rachel suggests making one with Ross, who claims he already has one with Phoebe... who is the one who suggested it to Rachel in the first place, claiming she has one with Joey. By the end of the episode, they settled on Ross being Rachel's backup, and Joey being Phoebe's.
** A variant in another episode; Chandler suggests to Monica that if neither of them are married by the time they're forty, they could have a child together. (This was [[HilariousInHindsight before they were dating)]]. It doesn't go like he expected.
--->'''Monica''': Why won't I be married when I'm forty?
--->'''Chandler''': Oh, no, no. No. I just meant hypothetically.
--->'''Monica''': Okay. ''Hypothetically,'' why won't I be married when I'm forty?
--->'''Chandler:''' No! No, no--
--->'''Monica:''' No, what is it? Seriously, is there something ''fundamentally un-marriable about me?''
--->'''Chandler:''' U-Uhhh...
--->'''Monica:''' ''Well?!''
--->'''Chandler''': ''(fumbles at back)'' Dear God, this- this parachute is a knapsack! ''(Rolls off of chair)''
* Carla Noll in ''{{Reunion}}'' is Aaron's best friend and hidden secret admirer for years. She's happy to hear him say that if they're still single in a few years that they'll marry each other.
* In one episode of ''Series/{{Frasier}}'', it sounds like Roz is about to suggest one of these, and Frasier agrees to marrying her if they are both indeed single at the time. [[SubvertedTrope Turns out]] Roz was going to suggest [[SuicidePact they kill each other]] instead.
* In ''Series/{{JAG}}'', Harm and Mac agree to have a child together if neither have a significant other some time in the future.
* In ''TheOffice'', Michael Scott suggests this to Pam (at least in terms of having a baby together) if they're still single in ten years. She shoots it down immediately... and, ever the salesman, he starts haggling. When he suggests that they do so if she's still single in ''thirty'' years, she [[OldMaid thinks about it for a very long time]] and agrees.
* On ''{{Series/Seinfeld}}'' Kramer proposes to Elaine that they marry each other if they're both still single at 60, and she accepts.
* Hudson and Mrs. Bridges - the butler and cook - of ''Series/UpstairsDownstairs'' have this arrangement. In one episode Mrs. Bridges seems to have found true love and Hudson offers to release her from their friendly agreement. Unfortunately her beloved turns out to be a jerk.
* ''Series/MurphyBrown'' has Murphy and Frank discuss the idea at a point when it seems like their romantic prospects are all but dead, but they let it drop and move on.

[[/folder]]

[[folder: Webcomics ]]

* Peejee proposes this to Davan in ''Webcomic/SomethingPositive'' as a way to guarantee neither of them grows old alone, which she is especially worried about as even their regular group of friends has largely gone their separate ways. Davan refuses, promising he'd never abandon her anyway [[spoiler:and shortly thereafter Davan meets Vanessa, whom he would eventually marry]]. It was the climax of a long bout of ShipTease the creator had [[TrollingCreator used to taunt the shippers who wanted Davan and Peejee together]], since them ''not'' getting romantically involved is one of the few iron-clad rules of the comic, promised to the real woman upon whom Peejee is based.

[[/folder]]

[[folder: Western Animation ]]

* Something of a parody in ''WesternAnimation/DrawnTogether'': Captain Hero and [[PowerPerversionPotential Unusually Flexible Girl]] were FriendsWithBenefits in college and promised that if they were still single at 30, they'd get married. She [[NewOldFlame shows up]] to collect.
* A variant in ''WesternAnimation/{{American Dad}}'': Stan asks his dentist to be his "back-up wife" in case he ends up outliving Francine. HilarityEnsues when Francine finds out and decides to get herself a "back-up husband" for the same eventuality, in the form of Stan's attractive younger colleague. Unfortunately, [[AxCrazy it turns out both would-be spouses are taking it a lot more seriously than either of the Smiths expected...]]

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