Opt-out and STOP handling
When a parent replies STOP to a school text, something happens that most district staff assume is a setting in their communications platform. It is not. The block is applied by the mobile carrier, before your platform is consulted, and no administrator anywhere can remove it.
| Keyword | Effect | Enforced by |
|---|---|---|
| STOP | Blocks further messages from that sender to that number | Carrier — not overridable by the platform or the district |
| STOPALL | Blocks messages from the sender across all of its campaigns | Carrier |
| UNSUBSCRIBE, CANCEL, END, QUIT | Recognised equivalents of STOP | Carrier |
| HELP, INFO | Returns the sender's identity and support contact | Carrier, answered from registered campaign text |
| START, UNSTOP, YES | Reverses a previous opt-out | Carrier — and only the subscriber can send it |
| Anything else | Passes through to the platform as an ordinary inbound message | Platform |
Why nobody at the district can undo it
Carrier-level opt-out is deliberately outside the sender's control, because a suppression list a sender could edit would be worthless. The consequence for districts is precise and worth stating to every principal who asks:
- The district cannot re-subscribe a number, however politely the parent asks in person.
- The vendor cannot do it either. If a vendor offers to, be concerned about what else they can do.
- Only the subscriber can reverse it, by texting START or UNSTOP to the same number from the handset that opted out.
The practical script for a front office is therefore short: "That block is held by your mobile carrier, not by us. Text START to the same number the school messages come from and it will lift. Meanwhile we will make sure your email and voice details are current." Print that on a card. It resolves the conversation in thirty seconds and it is true.
Districts should also capture the opt-out in their own records when they learn of one, whether it arrived by STOP, a phone call to the office, or a note on a form. Carrier-level state and district-level knowledge are different things, and only the second one lets you notice that a family has quietly gone dark.
What the block covers, and the cases that surprise people
| Situation | What is blocked |
|---|---|
| Parent texts STOP to the high-school number | That sender number only. The elementary school's different number still works. |
| Parent texts STOPALL | Every campaign from that sender, across all schools using it. |
| Two children, two schools, one shared number | Both children's messages, if both schools send from the same number. |
| Two guardians sharing one mobile | Both guardians. The block is on the number, not the person. |
| The district changes vendor and gets a new number | Nothing — the old opt-out does not travel. Families who opted out will start receiving messages again. |
| Email and voice channels | Nothing. An SMS opt-out says nothing about email or phone calls. |
That fifth row is a genuine compliance trap at migration. A new number means a clean carrier suppression list, and a family that clearly expressed a preference is suddenly receiving texts again. Carry your own opt-out records across, and honour them at the platform layer, because the carrier will not do it for you.
The emergency question, answered honestly
The question every communications director asks: if a parent has texted STOP, will they get the lockdown alert?
No. Not by SMS. The carrier block applies regardless of how urgent the message is, regardless of what your platform flags it as, and regardless of the TCPA emergency-purpose reasoning — that reasoning addresses whether you are permitted to send, not whether the carrier will deliver. Any vendor implying that their emergency flag punches through a carrier opt-out is describing something that does not exist.
Design for it in advance, because you cannot fix it in the moment. Three things, all of which are Tuesday-afternoon work rather than crisis work: keep a voice number for every family, since a text opt-out does not block calls; keep email current as a third path; and know the size of the opted-out population before an incident, so the gap is a known number rather than a discovery. In Kastr, emergency-flagged sends bypass per-family channel preferences and quiet hours and are gated behind a specific capability, but they cannot and do not bypass a carrier block.
The deeper prevention is not sending routine traffic on the emergency channel. Families opt out because they received nineteen messages about fundraisers. Every one of those messages purchased a small reduction in your ability to reach that family in an actual emergency.
Questions people actually ask
If a parent texts STOP, will they still get emergency alerts?
Not by SMS. The block is applied by the carrier and applies to all messages from that sender number, including emergency ones. Voice calls and email are unaffected, which is why every family needs a working second channel and why the opted-out population should be a number you know in advance.
How does a parent opt back in to school texts?
By texting START or UNSTOP to the same number they opted out from, using the same handset. Nobody at the district and nobody at the vendor can do it on their behalf, and a vendor claiming otherwise is misdescribing how carrier suppression works.
Can a district remove an opt-out on a parent's behalf?
No. Carrier-level suppression is deliberately outside the sender's control, because a list the sender could edit would provide no protection. The district's job is to record the opt-out internally and make sure another channel is current.
Does opting out of one school's texts opt a parent out of all of them?
It depends on the sending number. STOP blocks the sender number, so if every school messages from one number then yes; if schools have their own numbers, only that one is blocked. STOPALL blocks everything from that sender. Note also that a vendor change brings a new number and a blank suppression list, so old opt-outs must be carried over manually.
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