How to arm SMS reminders across a whole week of Google Calendar events

There is no shortage of add-ons that send an SMS reminder before a Google Calendar appointment. Almost all of them share the same assumption: that you have a handful of appointments, and you will happily open each one and set a reminder on it.

That assumption breaks the moment you are running a real schedule. At a hundred jobs a week, setting reminders one event at a time is an hour of clicking that you will stop doing by Wednesday. This guide covers arming a whole date range in one pass instead. If you only need to text one client about one appointment, start with how to send an SMS reminder to a client from a Google Calendar event.

Where do the phone numbers come from?

The thing that makes bulk possible is not the bulk button — it is not having to type a phone number for each event. If you already put the client's number in the calendar event, the number is read straight out of the event description.

A tagged number wins over anything else in the text. Write Mobile: 0491 570 156 and that is the number used. The recognised tags are PH, Mobile, MOB, TEL, PHONE and CELL, and you can change the list to match how your team already writes them.

If there is no tag, the description is scanned for anything that parses as a phone number in your country. This is why the tag matters more than it looks: a description containing Invoice 4155552671 will happily parse as a phone number, and an explicit Mobile: tag is what stops a reminder going to an invoice number. Numbers that can be positively identified as landlines are skipped rather than being sent an SMS that can never arrive.

Set up one message template first

A template is the message plus its timing. Timing is expressed as offsets in minutes before the event, and a template can carry several — the common setup is 1440, 60, which is one reminder the day before and another an hour before.

The message body fills in the event details automatically, so one template serves every client. Templates are managed in the web app and appear in the add-on's dropdown.

Arm a whole week in one pass

Open Google Calendar, open the Calendar Force panel, and use Bulk Set Reminders:

1. Pick a start and end date — a week, a fortnight, a month.
2. Choose the message template to apply.
3. Press Search Events to see what matched before anything is armed.
4. Untick anything you do not want. The list works as an exclusion list — everything found is going to be armed unless you say otherwise, which is the right way round when you are arming a hundred jobs and skipping two.
5. Confirm, and the rest get their reminder in one go.

Events that already carry a reminder are separated out rather than quietly re-armed, and you decide what happens to those at the next step — so running the same range twice does not double up on anyone.

Above 100 events in a single range the individual tick boxes are hidden, and only events with a detected mobile number are armed. That is a deliberate limit: the add-on panel has a hard ceiling on how many controls one card can hold, and silently dropping the tail of a long list would be worse than not offering the checkboxes. If you need to exclude particular jobs from a very large range, run it in smaller ranges.

There is also an override worth knowing about: instead of using the template's offsets, you can tick a box and give the whole batch one exact send time. That is the tool for “everyone booked this week gets a message at 4pm Friday” — an announcement rather than a per-appointment reminder.

How do you remove reminders from a whole week?

Bulk Remove Reminders takes a date range and strips the reminders back off those events, so when a week is cancelled or a run of jobs moves you are not hunting through a calendar disarming events one at a time.

There is a third button, Sync, for a subtler problem: events that were deleted or changed elsewhere can leave a reminder bell showing on a calendar for work that no longer exists. Sync reconciles the calendar against what is actually scheduled to send.

Setting a reminder on a single event

Bulk is the point, but not everything is bulk. Open any event in Google Calendar and the panel lets you set a reminder on just that one, pick its template, and edit the message body for that event alone without changing the template everyone else uses.

How much do bulk SMS reminders cost?

Reminders are paid for with credits, charged per message segment rather than per reminder. An SMS is 160 characters; a longer message is delivered as more than one segment and costs accordingly. If you are watching your spend, message length is the lever.

The panel shows three numbers: used, scheduled and available. Scheduled is the one people miss — reminders you have armed for future events have not been charged yet, but they are committed. If you arm more reminders than you have credit for, the panel warns you, and you cannot schedule beyond your balance rather than discovering the shortfall when messages silently fail to send.

Credit packs start at AUD 9.99 and there is no required monthly fee. A reminder that cannot be sent at all — no number, a landline, a number that has opted out — fails without using a credit, and if the SMS provider rejects a message or the carrier reports it failed, the credit is refunded to your balance.

What happens when a message does not get through?

If the SMS provider cannot take a message, Calendar Force tries again five minutes later, up to three attempts in total. Failures that can never succeed — an invalid number, a missing number — are not retried, because retrying them just delays telling you the truth. A failed reminder shows its error on the Reminders page, so a reminder that did not go out is something you can look up rather than guess at.

Once a message is handed over, the carrier reports back. A reminder then shows as delivered, or failed with the reason — and a failure the carrier reports refunds the credit. If the carrier never confirms either way it shows as no receipt: the message may still have arrived, so that one is not refunded.

Consent, and staying on the right side of it

How a client opts out depends on where they are. In the US, reminders come from a phone number, so recipients can reply STOP — that is honoured automatically across every Calendar Force sender, and replying START opts back in. In Australia, reminders come from the sender name CalForce, which cannot receive replies, so a client who wants them to stop will tell you directly: remove the reminders for that client and take their number out of the event description so none are armed again. This is not a nicety: unsolicited commercial SMS is regulated in most countries, and reminders for an appointment someone actually booked sit on the right side of that line only while opt-outs are respected.

Which countries does it work in?

SMS reminders are live for Australian and United States numbers, and the two work slightly differently.

Australian reminders come from the sender name CalForce. US reminders come from a US phone number, and each one starts with “CalendarForce:” and ends with “Reply STOP to opt out.” — both added automatically, as US carriers require, and both counted in the message length.

US carriers also require a record that your client agreed to receive texts before the first one is sent. Open the event in the Calendar Force panel and use Record consent, which asks how consent was obtained — verbally at booking, on a booking form, or on a web form. You only do this once per number. A bulk run skips any US number with no consent on file and tells you how many it skipped, so a missing record shows up as a count rather than a reminder that silently never goes out.

For other countries, check with us before relying on reminders. The invoicing and rostering side of Calendar Force works anywhere.

Summary

1. Put the client's number in the event description, tagged — Mobile: …
2. Build one template with offsets like 1440 and 60 minutes.
3. Bulk Set Reminders over a date range, search, confirm.
4. Bulk Remove when a week changes; Sync to reconcile.
5. Watch the scheduled figure, not just available.

Calendar Force is a Google Workspace Marketplace add-on plus a web app. Once your week is armed, the same events can generate your invoices as well. See pricing.