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SMS ​

SMS reaches every phone — feature phones, dumb phones, any handset that can take a SIM. That makes it the channel of last resort for messages that absolutely must arrive: meeting cancellations, urgent updates, password recovery links. Open rates rival WhatsApp.

Cost per message is higher than WhatsApp or email, so most churches reserve SMS for urgency rather than weekly comms.

SMS send screen

Set up a provider ​

Configure a provider in Settings → Channels before sending:

ProviderCoveragePricing model
Twilioglobalper-message, varies by country
smsmobileapistrong in Africa + Caribbean + LATAMper-message

You'll need an account with the provider and an API key / token. Paste it into the channel config and run the test-send to confirm.

Send a single SMS ​

From a member profile:

  1. Open the message action.
  2. Pick SMS as the channel.
  3. Compose. Plain text only — no formatting, no inline images.
  4. Send.

Most SMS providers count characters and split messages over 160 characters into multiple segments (billed individually). The compose window shows a live segment count.

Send a bulk SMS ​

From Messaging → Send:

  1. Pick recipients (filter, list, or pasted numbers).
  2. Choose SMS.
  3. Compose — watch the segment count.
  4. Send.

For bulk, GCM throttles per the gateway's documented per-second rate so you don't get blocked. Twilio's default is 1 message per second per sender; smsmobileapi varies.

TIP

A 1,000-recipient SMS bulk at 1/sec takes ~17 minutes. Plan accordingly for time-sensitive announcements.

Sender ID ​

Different providers have different rules for what shows in the recipient's From:

  • Twilio US/UK — a leased phone number.
  • Twilio in some countries — an alphanumeric sender ID (e.g. GraceChurch).
  • smsmobileapi — depends on country.

Configure the sender in the channel settings. If you're sending internationally, you might need different sender IDs per country — Twilio supports that with their messaging service.

Opt-out handling ​

Most SMS regulators require opt-out support. We add Reply STOP to unsubscribe to every bulk SMS automatically (length permitting).

When a recipient replies STOP:

  • The provider flags them as opted out on their side.
  • Our inbound webhook receives the STOP and adds the member to the SMS unsubscribe list.
  • Future bulk sends skip them.

You can review the unsubscribe list from Messaging → Unsubscribe.

WARNING

You cannot bypass opt-out by switching channels. If a member replied STOP to SMS, they're only blocked from SMS — they might still be reachable on WhatsApp or email. Be respectful and stop messaging them entirely if they've made it clear.

Replies ​

For two-way numbers, replies appear in Conversations. For one-way sender IDs (alphanumeric), recipients can't reply — they can only opt out via the STOP keyword.

Check your provider docs for whether your sender ID is one-way or two-way.

Cost monitoring ​

Each SMS provider has its own pricing. Twilio in particular has wildly different per-message rates across countries. Watch your Settings → Channels → Usage screen for monthly spend.

TIP

For an unexpectedly large send, the cost can be sobering. A 10,000-recipient international SMS bulk can easily cost more than your monthly GCM subscription. Pre-calculate via the segment count and your provider's per-message rate before clicking send.

Common questions ​

Why don't my members receive SMS? Common causes: invalid number format, provider account not topped up, recipient on a blocked carrier, or they opted out (STOP). The communication log shows the provider's error code for failed sends.

Can I send MMS (with images)? Twilio supports MMS in the US. Most other providers and countries don't. We'll send the text and skip the attachment if the provider doesn't support MMS.

Does SMS work for password resets? GCM uses email for password resets, not SMS. SMS is for member comms, not auth flows.

Next steps ​