Forum Discussion
SMS Stop working
My APP is sending sms to registered customer, every once in awile SMS stops working for an hour or two. What would cause that?
Business. I am throttling to 1 SMS every 1.2 seconds and still get cut off every once in while. When an alarm occurs we may send 10-15 SMS depending on what the customer as requested
It might be worth reaching out to support to see if they can find anything on the backend causing this.
Was hoping technical support was monitoring this
I tried, never got to someone technical enough. They all make me do some basic test, remove battery, restart and end up saying it is the phone
- SuperFred
Community Manager
I can't make any promises but I'll be back online tomorrow and I can try to reach out to a friend who use to be level 3 support. However to make it easier, I would you to write me a resume of the issue, the app involved, what you normally do when it works etc. I'll copy/paste your message and reach out to my friend. I'm sorry for asking this since it may take few minutes to explain everything but I have faith in my friend's expertise.
tks!
We’ve developed an Android application that transmits alarm notifications via SMS to registered contacts whenever an elderly person requests help. The app relies strictly on standard SMS (RCS is disabled) and typically works as expected.
However, every day we encounter recurring delivery outages: SMS sending suddenly stops for a period of about 45–60 minutes. During this time, both our app and the built-in Android messaging app are unable to send SMS messages (they remain unsent or stuck in the outbox). When the outage resolves, it always resumes exactly on the hour (e.g., if SMS stops at 07:15, service resumes at 08:00).
Other phones on the same network continue to send SMS normally, which rules out a general Telus outage. The issue appears tied to our sending pattern: while our daily SMS volume is modest, alarms can generate bursts of many SMS in a very short window (one alarm → multiple recipients). This suggests the device or the carrier network is applying a rate-limiting or anti-spam control that temporarily blocks outgoing SMS when thresholds are exceeded.
All of our outbound messages are fully compliant with anti-spam practices: every SMS includes the required opt-out language (e.g., “Reply STOP if you don’t want to receive any more messages”). Despite this, the blocking still occurs.
Interestingly, the problem does not occur when using Twilio SMS; only when sending through the Telus SIM/network on our devices.
What exact Telus rules or thresholds are triggering these temporary blocks?
Are they based on messages per hour, per minute, per recipient, or identical content sent in bursts?
If we knew the policy, we could mitigate it by throttling, queueing, or adding delays between SMS sends. Without that visibility, we’re blind.
Insist on level 2 or a manager. You definitely want to get past the foreign call centre people.
