Send SMS messages to a group via AWS SNS

For Terraform versions >= 0.12 use versions tagged 0.5.0 or later, for Terraform 0.11 use 0.4.0.

Create a main.tf file with the following contents:

# main.tf

module "group_sms" {
  source                 = "amancevice/group-sms/aws"
  monthly_spend_limit    = 100
  topic_name             = "my-topic"
  topic_display_name     = "MyTopic"
  usage_report_s3_bucket = "<my-sms-usage-bucket>"

  subscriptions = [
    "+19876543210",
    "+12345678910",
    "+15555555555",
    "..."
  ]
}

The catch to all this is that Amazon imposes a strict $1/month limit on SMS messages. The only way to raise that limit is to make a request to Amazon and wait for them to allow you to spend over that limit.

Raising your SMS limit is as simple as filing a support ticket with AWS. When I opened mine I was contacted within a few days by an Amazon Rep.

Our limit was increased to the desired amount after answering the following questions for the Rep:

The spending limit you are requesting, in US dollars.

It's probably best for you to do some back-of-the-envelope calculations for this. How many texts will you send per month? To how many people? Try to overshoot by a large margin so that you don't have to do this again.

A list of countries in which the recipients of your messages are located.

We have some members with Canadian phone numbers (apparently) so I indicated that we would be contacting US & Canadian phones to be on the safe side.

Information about the type of messages you will be sending (Transactional, Promotional, One-Time Password, etc.)

Promotional messages are what you are looking for here.

The maximum number of messages you expect to send per day.

We have no intention of spamming our members, so I said "between 0–2 per day, mostly 0" to give some wiggle-room.

What is the name of the website, application, or other entity that will be sending SMS messages? Please provide a link.

I explained that the messages would originate from our private Slack workspace.

Explain the opt-in process to receive your messages.

Here I explained that members are given the opportunity to provide a phone number when they join the org as dues-paying members.

Describe the primary function of your site or application and how SMS will be incorporated.

This one is up to you.

Details of the ways in which you will ensure you are only sending to people who have requested your messages.

Again I explained that we only have contact info for members in good standing and that we would be respecting Amazon's built-in opt-out protocols.

Users who respond to any SMS with STOP, UNSUBSCRIBE, END, etc are automatically removed from distribution.