How to send a wake-up call to someone else's phone

There are two very different questions hiding behind this search, and which one you’re asking changes the answer completely.

The first is “my friend asked me to wake them up at 5am and I’d rather not set my own alarm for 4:55.” That’s a favour, and there are free ways to do it.

The second is “I want to make someone’s phone ring at a time they haven’t agreed to.” That one has a short answer: don’t. It’s worth getting that out of the way before the tools, because the tools are the easy part.

A phone ringing at an hour it shouldn’t is frightening. Someone woken by an unexpected call assumes, in the two seconds before they answer, that something has gone badly wrong. That reaction doesn’t soften with repetition — it just turns into resentment.

There’s a legal edge to it as well as a social one. Automated and repeated calls to a number whose owner hasn’t agreed to receive them are regulated in most countries — in the US that’s the TCPA, and every reputable service builds the same rule into its terms. Ours says it plainly: do not use ReminderCall to call or text anyone who has not consented, and set up reminders only for your own number or a number whose owner has agreed to receive them. Every service on this page has some version of that clause, and a free dialer that doesn’t have one isn’t being generous — it’s being careless with your problem.

So the working version of this task is: they’ve asked you, or you’ve asked them and they said yes. Agree the time, agree which days, and agree how they cancel it — “text me the night before if you don’t need it” is enough. Arrangements like this outlive the reason for them, and an unwanted 5am ring is the fastest way to end a favour.

If the person you want to wake hasn’t agreed, the honest advice is to talk to them, not to route around them with software.

The thing nobody mentions: a call from an unknown number may not wake them at all

This is the part that quietly sinks most attempts, and it applies to every option below.

Incoming calls follow the phone’s ring settings rather than its notification settings, which is why a call gets through a silenced phone when a text doesn’t. But that’s not unconditional. On an iPhone with Do Not Disturb or a Sleep Focus active — which is most phones, most nights — calls from numbers that aren’t saved contacts are silenced by default. Android’s Do Not Disturb behaves much the same way. So an automated call from a service’s outbound number lands on a sleeping phone as a missed-call badge they’ll find at 9am.

There are exactly two fixes, and both require the sleeping person to do something in advance on their own phone:

Save the number as a contact, so it falls under “Allow calls from contacts” rather than being treated as a stranger.
Turn on Emergency Bypass for that contact (iPhone: Contacts → Edit → Ringtone → Emergency Bypass), which makes it ring through silent mode and Focus regardless.

There’s no way to do this from the outside. iOS gives apps no ability to set or read Emergency Bypass, so no service can promise to ring through a stranger’s silenced phone — it’s a one-time setup on the receiving handset or it doesn’t happen. Untouched by that setup, a hard-muted phone will at best vibrate with a full-screen call, which is not a reliable wake-up. We wrote the whole mechanism up in reminders that work when the phone is on silent; it’s worth five minutes before you rely on any of this.

Practical consequence: if the arrangement is recurring, do the contact-and-bypass step together on the first day. If it’s a one-off tomorrow morning, assume the call may not break through, and back it up with their own alarm.

Option 1 — just ring them yourself

Free, immediate, no account, and genuinely the best option for a one-off.

It also has one advantage nothing automated can match: a real human voice on the line is hard to fall back asleep through. An automated message plays whether you’re conscious or not; a friend saying your name and waiting for an answer keeps you awake through the first thirty seconds, which is the part that decides whether you get up.

The catch is obvious. It requires you to be awake and reliable at that hour. Fine for the morning of someone’s flight. A poor foundation for anything recurring, because the first time you sleep in, so do they. If you’re doing this across an offset, the arithmetic is its own trap — waking someone up in a different time zone covers the daylight-saving problem that catches people twice a year.

Option 2 — a free web dialer that accepts any number

This is the closest thing to what the search is literally asking for: a web form where you type in a phone number and a time, and a robot rings it. No app on either end, no signup, no cost.

WakeUpDialer is the name people remember, and a handful of similar services (Snoozester, WakeUpLand, betterwakeupcall) do the same job. They will happily dial a number that isn’t yours — which is precisely why the consent rule above matters more here than anywhere else.

Two honest warnings:

Reliability is not promised, and shouldn’t be assumed. These are best-effort free services, usually run by one person, and their own disclaimers say so. WakeUpDialer in particular has a long trail of reports that its calls quietly stopped arriving while the booking form kept accepting bookings — we went through the current state of it in Wake Up Dialer alternatives. Test any of them on a morning where oversleeping costs nothing.
You’re giving someone else’s phone number to a third party. That’s their data, not yours. Ask first.

For a single low-stakes wake-up where the person has asked you and has their own alarm as backup, a free dialer is a perfectly sensible answer and you should use it rather than paying for anything.

Option 3 — an app installed on their phone

Galarm and a few similar apps are built exactly for this: you and the other person both install the app, connect as contacts, and you can set an alarm that fires on their device. Because it’s an alarm rather than an incoming call, it rings through silent mode without any contact-and-bypass setup — that’s the real advantage, and it’s a significant one.

The cost is coordination. It only works if they install it, keep it installed, keep notifications enabled, and stay signed in. For a willing partner, roommate or teammate, that’s a fair trade. For anyone who is vague about phone admin — which includes most people you’d be worried about oversleeping — the setup is the thing that fails, not the alarm.

Where ReminderCall fits, and where it doesn’t

Being straight about this, because it’s the reason you’re on our site and not a competitor’s:

ReminderCall cannot send a call to someone else’s phone from your account. There is no recipient field. The app dials the phone number the account itself is registered to — the number you verified by text when you signed in — and nothing anywhere in the product lets you type in a different one. If you’re signed in with your number and you want your friend’s phone to ring, we can’t do that, and no setting will change it. Use option 1 or 2 above.

What we do fit is a narrower case, and it’s worth naming because a lot of people arrive here wanting it:

A standing arrangement with someone who has agreed to it, where the account is registered to their number. You set the account up on their number — the verification text goes to their phone, so they have to be part of the setup, which is a feature rather than a bug here. From then on, their phone gets a real call at the time you scheduled, with your message read aloud, every morning or on chosen weekdays. Nothing has to be installed on their handset; the app itself can live on yours. This is the same mechanism behind calling an elderly parent, and the same limit applies: the number has to be one that can receive a text at signup, so a landline can’t be enrolled at all.

That trade only makes sense for something recurring and agreed. For “wake my mate up once tomorrow,” it’s a bad deal and a free dialer is the right answer.

Two caveats even in the good case. Do the save-the-contact and Emergency Bypass step on their phone on day one, or the call may be silenced by their overnight Focus like any other unknown number. And treat the call as a layer over their own alarm rather than a replacement for it — it travels over a phone network nobody in the arrangement controls, at an hour when nobody is awake to notice a failure.

ReminderCall is a reminder service, not an emergency or medical device. If the reason you need someone’s phone to ring is that their health or safety depends on it, a scheduled call is the wrong tool — a person who can physically get to them is the right one.

The bottom line

Ask them first. That’s the whole first half of this problem, and it’s the half that software can’t help with.

Then pick the lightest thing that works. One-off favour: ring them yourself, or book a free web dialer and tell them to keep their own alarm set. Ongoing arrangement with a willing person: either an app on their phone like Galarm, or a scheduled wake-up call to a number the account is registered to — ReminderCall does the second one.

And whichever you choose, spend the two minutes getting their phone to treat the incoming number as a contact. A call that gets silenced at 5am is the same as no call at all.