How Does an IF Work? Every Situation, Explained
Entry No. 053 ·
By The IF Team
An IF is a private, sealed message of up to 250 characters that you send on the IF dating app to someone you have feelings for when the timing is wrong — usually because one of you is in a relationship. They may be told an IF is waiting for them, but not who sent it or what it says. It opens only when you are both single: you become single, they do, or you both do. Once it opens, they choose to accept or decline, and accepting starts a chat with your IF as its first message. Until then, no conversation can open.
It is made for a particular feeling: the one you have carried for years for the friend you met at university, who had a partner then and has one now. A feeling like that is honest, and nothing to be ashamed of. You could tell them face to face, but that has real risks; an IF lets you say it now and have it wait, so that if the timing ever lines up, you are already there. What happens to your IF depends on which of you is single and whether they are on IF at all, so here is every combination: what each of you sees, when an IF reveals, and how one can end.
How the IF dating app works, in one rule
IF is a dating app for everyone, single or in a relationship, and your relationship status, which you set yourself, changes what you can do. Two single people use IF like any dating app: they can Like each other, and an accepted Like opens a chat. If either of you is marked as in a relationship, the only thing you can send is an IF.
Underneath everything sits one rule: no Like, match or chat is possible while either of you is marked as in a relationship. An IF is a sealed note, never a conversation, and every path to opening one runs through both of you being single. That is why IF can welcome people in relationships as well as singles without ever becoming a way to cheat. Having IF on your phone while you are with someone is not cheating, and neither is sending an IF. Marking yourself in a relationship clears your Likes and chats, but you keep your account, so IFs can still reach you. We call it making it IF official.
One honest caveat: IF does not verify anyone’s status. It is self-declared, shown on every profile card, and IF’s Community Guidelines ask everyone to keep it true. And an IF is for saying how you feel, not for keeping tabs on anyone’s relationship: send it for the words, then let it do the waiting while you get on with your life.
Who you can send an IF to
You can send an IF to someone single, someone in a relationship, or someone who is not on IF yet. You can reach them on Swipe, where every card carries a status badge, or on Search, by the email address, phone number or Instagram handle they gave you.
Nobody is notified when you search for them. An IF sent through Search must include a message, and if Search finds nobody and you send one anyway, you need a verified phone number on your account. Use only details the person shared with you themselves; if you would have to dig for someone’s number, that is your answer.
If you are both single and you can find them on IF, an IF is not an option: you send a Like.
What they see when an IF arrives
If they are on IF and have notifications on, a push tells them “You received an IF” and “Your timing might be right”, and an email may follow: “Someone sent you an IF on IF.” Neither names you or shows your message. In their list, the IF usually appears as a sealed card that reads “Hidden — ready for when the timing is right”. Since they cannot see who it is from, all they can do with it is keep it or delete it; the one exception, when you are both single, is explained below.
An IF is sealed, not secret: a partner who glances at their phone could see that notification too, and people can sometimes guess from context who sent an IF. IF never discloses the sender before a reveal, but it cannot stop anyone wondering. None of that makes an IF something to hide: it is a feeling, said once and written down. If you are the one holding a sealed card, what it means to receive an IF is written for you.
When does an IF reveal? Every situation at a glance
One question decides most of what follows: which of you was single first. If you were single and waiting when they became single, the last word is yours. If they were single first, your own status change decides.
- You are single, they are in a relationship: it waits. If they become single while you still are, you get 24 hours to reveal it.
- You are in a relationship, they are single: it reveals the moment you mark yourself single, as long as they still are, with no window.
- You are both in relationships: it waits for whoever becomes single first, then follows one of the two rules above.
- You are both single and you can find them on IF: send a Like instead.
- You are both single, but Search cannot find them: if they are on IF, they can tap Notify, which gives you 24 hours to reveal.
- They are not on IF: it waits in case they join. An email address gets one short invitation; a phone number or Instagram handle, nothing.
You are single, they are in a relationship
Your IF waits. Nothing happens while they stay in their relationship, and nothing is asked of them. The compose screen spells out the deal: “they’ll only see it if they become single — and only if you still want them to”.
If they mark themselves single while you are still single, you get a push: “Your IF can be revealed” and “You have 24 hours to approve.” Their card changes to “Hidden — awaiting sender reveal”. Tap Reveal within those 24 hours and they see your profile and your message. Let the 24 hours pass and the IF lapses: they never see your name or your message, and IF never tells them it was you.
You are in a relationship, they are single
This one reveals the moment you change your own status to single, as long as they are still single. There is no 24-hour window and no second confirmation; the compose screen puts it simply: “they’ll only see it if you become single”.
Sending one while you are with someone can be entirely honest. Feelings for someone else do not make you a bad partner or a bad person, and you can send an IF whatever you feel about your own relationship, because nothing can open until you are both single. The only lines are the ones that apply everywhere: no cheating, and no lying, to your partner or to yourself. If you are still working out what the feeling means for the relationship you are in, our guide to having a crush while you are in a relationship walks through it.
You are both in relationships
The compose screen reads “they’ll only see it if you both become single”, and the IF waits for whoever gets there first. If you become single first, it behaves like the first situation above: when they later become single too, you get your 24 hours to reveal. If they become single first, it behaves like the second: it reveals the moment you mark yourself single.
You are both single
If you can find them on IF, you cannot send them an IF. You send a Like, and if they accept it, a chat opens. An IF exists for timing that is wrong; when the timing is already right, you can simply say hello.
You are both single, but Search cannot find them
Sometimes you search for an email address, phone number or handle and nobody comes up. The person may not be on IF, or may have turned off “Discoverable in Search”, which makes them look exactly like someone who is not there. You cannot tell which, by design, and you can still send an IF.
If they are on IF and single, and so are you, they see a card that reads “Someone thinks you’re in a relationship — let them know you’re single”, with two buttons: Notify and Delete. Only Notify starts the clock. You then get the same “Your IF can be revealed” push, and 24 hours to reveal it or let it lapse. If they tap Delete, it is gone. If they do neither, it simply keeps waiting.
They are not on IF yet
If you searched with an email address, IF sends one short invitation email, unless that address has unsubscribed, with the subject “Someone has something to tell you” and a one-click unsubscribe. It does not say who you are. If you used a phone number or Instagram handle, nothing is sent at all: IF never texts or messages the person you wrote to. Your IF simply waits. Its card then offers Confide in Mutuals: a ready-made message you can send to mutual friends, asking them to drop a hint that a message is waiting for your crush, and a line you can post on your socials. What you share, and with whom, is your choice.
If they later join IF with that email address or phone number, or link that Instagram handle, your IF is there for them, and it follows whichever of the rules above fits your two statuses at that moment.
After the reveal: accept or decline
When an IF reveals, they get a push that reads “An IF just revealed” and “See who it’s from.” They see your profile and your message, and they choose.
If they accept, a chat opens with your IF as its first message, headed with your name and the date you sent it, and you get a notification: “They accepted your IF”. However long it waited, the conversation starts with the words you wrote.
If they decline, you are not told. The IF simply leaves your list. That silence is kind to both of you. Turning someone down is hard on the person saying no as well: when researchers collected accounts of unrequited love, the people doing the refusing often felt guilty and unsure how a refusal was supposed to go. A quiet decline spares them that, and spares you a conversation neither of you needs. It is also an answer: IF’s Community Guidelines ask you never to contact someone through other means after they decline.
The ways an IF can end
An IF does not have a fixed expiry date. It waits until you are both single, and it can end in a few ways, including:
- Accepted: a chat opens.
- Declined: you are not told, and it leaves your list.
- Deleted by them before it reveals: it leaves your list, and you are not told why.
- Lapsed: the 24-hour reveal window passes without you tapping Reveal, and you stay hidden for good.
- Withdrawn: on the IF and IFinity plans you can withdraw an unrevealed IF, and you stay hidden for good.
- Blocked or banned: if either of you blocks the other, or either account is banned for breaking IF’s Community Guidelines, the IF is taken down.
- Either account is deleted: the IF goes with it.
Most of the time, it simply waits, sealed.
Is there an app to tell someone you like them when they’re in a relationship?
Look for a way to tell someone who is taken how you feel, and you will find very little. The nearest thing, as of September 2026, is Facebook Dating’s Secret Crush, where Facebook still offers it: you add up to nine Facebook friends or Instagram followers, and it is a match only if one of them uses Facebook Dating and adds you back. It is built around mutual interest, not around timing.
The pull to say something is understandable. In research on regret, people’s actions stung more in the short term, but it was the things they had not done that they regretted most in the long run. An IF is built for the space between saying nothing and saying too much: you put the feeling into words, IF keeps those words sealed until you are both single, and nothing is asked of them today.
If the feeling has started to take over your days, talking it through with someone can help. And when you do, here is how to put it into words.
Where IF fits
Whether to say something, and how, is always your call. You can tell them face to face, and sometimes it goes well. But opening up like that has risks: it asks them to respond, there and then, to something they may not be in a position to answer; a friendship can feel different by the next morning; and words said out loud cannot be taken back. You are potentially better off sending an IF. It says everything and asks nothing of them today, and if the timing ever lines up, you are there to show them how much you have always liked them. Our guide to a crush on someone who is taken weighs telling them against every other option.
An IF can also be a release valve. A feeling you have rehearsed in your head for months gets written down once, in 250 characters, and put somewhere safe. You stop carrying it alone, and you keep living your life while it waits.
Your first IF is free. Finding the words takes some nerve, but once they are written, the hard part is done. Sending one is emotionally brave, and maybe it leads you where you were meant to be all along.
Questions people ask
Can their partner see that they received an IF?
They could see that one arrived. If notifications are on, the push reads “You received an IF”, so a partner glancing at the phone might see it. IF never shows who sent it or what it says until it reveals, and it can reveal only once you are both single.
Does an IF expire?
Not on a timer. The only clock is the 24-hour reveal window, which opens only when you are single and they become single, or when they tap Notify. Otherwise an IF waits until you are both single, and they are free to delete it before then. On the IF and IFinity plans you can also withdraw it.
Can I withdraw an IF?
On the IF and IFinity plans, yes: you can withdraw an unrevealed IF, and you stay hidden for good. Without a paid plan you cannot take one back, but if you are single when they become single, nothing reveals unless you tap Reveal within the 24 hours. The membership page sets out what each plan includes.
Will they know an IF is from me?
Not from IF, until it is revealed. They may be told an IF is waiting, but never who sent it or what it says before then. However, they can still guess from context.
Is sending an IF free?
Your first IF is free. Receiving and revealing IFs, Likes, matching and chatting are free too. The membership page sets out what the IF and IFinity plans add.
If the feeling is right and the timing is not, say it once and send your IF. Right person, wrong time? Wait for them on IF.