Ignoring STOP is the worst-looking mistake in texting. It's a violation with no ambiguity, the person told you to stop and you kept going, so it's the easiest case a plaintiff can bring. At $500 to $1,500 per message with no cap, a broken opt-out process multiplied across a list is a serious liability.
It's also a deliverability killer
A person who said STOP and got texted anyway doesn't just have a claim, they report you. Those complaints tell the carriers your traffic is unwanted, which is how a compliance failure becomes a filtering failure that takes your whole program down.
Make STOP automatic
Opt-outs can't be a manual task someone handles later. The instant a recipient replies STOP, the system must remove them permanently, before the next send, and keep the record that it did. Reliable, automatic STOP handling is the single control that prevents the worst allegation in the book.
Frequently asked questions
What's the penalty for texting after someone opts out?
$500 to $1,500 per message under the TCPA, with no cap, plus spam reports that damage deliverability. Texting after STOP is the clearest violation to prove.
How do I make sure STOP is honored?
Use a platform that enforces opt-outs automatically and permanently the moment STOP arrives, and keeps the record. Don't rely on manual list management.
Informational, not legal advice.
Keep reading: STOP and HELP: handling opt-outs the right way and The cost of non-compliance.