Can I send a reminder to someone else's phone?

Short version: usually not from inside a reminder app. Almost every reminder app — ours included — sets reminders for the phone that’s signed in, and has no field anywhere for someone else’s number. What you actually want is one of four things that already exist on the phone in your hand, and three of them are free.

Here they are in the order most people should try them.

Option 1 — just text them

It sounds too obvious to be the answer, and it’s the answer more often than not.

A text needs no app on their end, works on every handset ever made, costs nothing, and arrives with your name on it rather than a robot’s. If the reminder is “don’t forget the passport tomorrow,” a text at the right moment is a better reminder than anything automated, because it comes from a person they’ll feel slightly bad about ignoring.

The only real limitation is that you have to remember to send it. Which is fine — set a reminder on your own phone to text them. That’s the trick most people miss: you don’t need to reach into their phone at all, you need your own phone to poke you at the right time so you can. Every reminder app on earth does that, and it sidesteps the entire problem.

For anything recurring where you’ll actually be around — a weekly nudge, a monthly bill — this is the whole solution and you can stop reading here.

Option 2 — a shared reminder list (the built-in answer)

Both phone platforms have this already, and it’s what most people searching this are really looking for.

On iPhone, Apple’s Reminders app lets you share a whole list. Open Reminders, pick or create a list, tap the person icon at the top, and send an invitation via Messages. Once they accept, either of you can add items, and you can assign a specific reminder to them — it then fires as a notification on their device, at the time and place you set. Assigning works on iOS 13 and later on both ends.

On Android, Google Assistant does the equivalent for family members. If you’re in the same Google Family Group, you can say “Hey Google, remind Dad to take the bins out at 7pm” and it will notify him on his devices. Outside a family group, it’s more limited than people expect — this is a household feature, not a general-purpose way to ping anyone.

The catch on both, and it’s the one that decides whether this works for you: they have to accept the invitation, and they have to keep notifications on. You are not sending a reminder to their phone so much as being granted permission to add to a list they already watch. If the person is engaged and wants your help, this is excellent and free. If they’re the sort of person who has 4,000 unread notifications, an assigned reminder joins the pile.

Option 3 — a shared calendar event with an alert

If the thing has a time — an appointment, a flight, a call — this is quietly the most reliable free option, and it’s underused.

Create the event in Google Calendar or Apple Calendar, invite them as a guest, and set a notification on it. Once they accept, the event sits in the calendar they already check, and their own phone fires the alert. It survives them changing phones. It shows the details, not just a nudge. And unlike a reminder assigned out of the blue, an invitation is a normal thing to receive, so the social friction is zero.

It’s the wrong shape for “take your tablet at 8pm every day” — a recurring calendar alert for a daily habit gets tuned out fast. But for anything with a date attached, try this before installing anything.

Option 4 — an app on their phone, built for exactly this

If the free routes don’t fit, there’s a category of app designed for reminding other people: Galarm is the best-known, and Hound Reminders and a few smaller ones do the same job.

The model is that you both install the app and connect as contacts. Then you can set a reminder or alarm that fires on their device. Because it fires as a local alarm rather than an incoming call or a shared list item, it rings through silent mode without any setup on the receiving end — which is a genuine advantage over everything else here.

The cost is coordination, and it’s the whole cost. 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 and Galarm is a good app. For someone who is vague about phone admin — which, be honest, is usually the person you’re worried about forgetting things — the setup is what fails, not the reminder.

Before you set any of this up: get their agreement

This is not a formality paragraph, and it’s the difference between a favour and a nuisance.

Reminders you didn’t ask for are irritating in a way that compounds. The first one is thoughtful. The fifth one, at a time that no longer suits, from a system they can’t easily turn off, reads as nagging — and the person on the receiving end will usually blame you rather than the software.

There’s a legal edge to it too, and it’s sharper than most people realise once automated calls or texts are involved rather than notifications. In the US, repeated automated calls to a number whose owner hasn’t consented fall under the TCPA. Our own terms say it plainly: “Do not use ReminderCall to call or text anyone who has not consented. Set up reminders only for your own number, or a number whose owner has agreed to receive them.” Every reputable service has some version of that clause. A tool that lets you type in any number without one isn’t being generous with you — it’s leaving the responsibility on you.

So the working version of this task is always: they’ve asked you, or you’ve asked them and they said yes. Agree what the reminder is, when it fires, and how they turn it off. Arrangements like this outlive the reason for them.

If the person hasn’t agreed, the honest advice is to talk to them rather than to route around them with software.

Where ReminderCall fits — and where it doesn’t

Being direct about this, because you’re on our site and not a competitor’s:

ReminderCall cannot send a reminder from your account to someone else’s phone. 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 in the product lets you type in a different one. There’s no share feature and no invite feature. 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 one of the four options above.

What we do fit is narrower, and worth naming because a fair number of people arrive here wanting exactly 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 phone number — the verification text goes to their handset, 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, on the days you choose. Nothing has to be installed on their phone; the app can live on yours. That’s the same mechanism behind calling an elderly parent and a daily reminder call for Mom, and it carries the same limit: the number must be able to 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 “remind my mate about the thing tomorrow,” it’s a bad deal — text them.

One caveat even in the good case, and it applies to every incoming call: on a phone with Do Not Disturb or a Focus active, calls from numbers that aren’t saved contacts are silenced by default. Save the calling number as a contact on their phone on day one, and turn on Emergency Bypass for it if the timing matters. We wrote the mechanism up in reminders that work when your phone is on silent.

ReminderCall is a reminder service, not a medical or emergency device. For anything where health or safety depends on the reminder landing — critical medication especially — pair it with a verification layer: a pill organiser you can see at a glance, a pharmacy blister pack, or a person who checks. A scheduled call travels over a phone network nobody in the arrangement controls, and no reminder system should be the only thing standing between someone and a missed dose.

Wake-ups are a different problem

If what you actually want is to make someone’s phone ring at 5am so they don’t oversleep, the tooling is different — free web dialers that accept any number are the main answer there, and they don’t apply to task reminders. That’s covered separately in how to send a wake-up call to someone else’s phone.

The bottom line

Ask them first — that’s the half of this problem software can’t solve.

Then pick the lightest thing that works. One-off: text them, and set a reminder on your own phone to do it. Something with a date: send a calendar invitation with an alert. A recurring household arrangement with a willing person: a shared Reminders list, or Galarm on both phones. A standing daily call to someone who agreed and whose number the account is registered to: that’s the narrow case ReminderCall is built for.

And whatever you choose, remember that the reminder has to land on a phone that’s paying attention. A notification in a pile of 4,000, or a call from an unknown number at midnight, is the same as no reminder at all.