Don’t reply - that can be used to confirm your number is real. That info is used and resold to spam you even more. Also the STOP keyword works only on some source phone numbers technically.
In the US you can report the spam texts by forwarding the message to 7726 (“SPAM” on your keypad) at which point your carrier will text you back and ask for the source number. This doesn’t report the message to the government agencies but just your carrier, so they can hopefully punish the platforms sending spam.
Use a site like https://www.freecarrierlookup.com/ to see which carrier or platform sent it, which is useful for the next step of reporting offenders.
Now report the incident at the FTC and FCC websites. Do this every single time so it eventually creates difficulties for the platforms enabling this. Mention the carrier or platform carrying the spam. Put in all the details correctly.
If it is an iMessage you should use the built in “report junk” feature.
You can also go to the website of the platform that carried the message to report things through their abuse reporting pages, but not all of them are diligent. Some are happy taking money from spammers to abuse you, and will make you keep reporting each phone number that spams you because they do nothing about it except block that one number from contacting you. They won’t fix the underlying root cause of why they have all these illegal abusers as customers.
My personal experience is that the vast majority of text spam comes from a few offending text messaging platforms - for example Sinch (https://en.wikipedia.org/wiki/Sinch_AB) and Bandwidth (https://en.wikipedia.org/wiki/Bandwidth_Inc.) for example. These are potentially seemingly commercial platforms for spammers. Note that Sinch owns Mailgun and Mailjet too and has a long documented history of legal trouble due to spamming. Businesses should avoid using these platforms because their own reputation and delivery will be affected by being mixed with spammers.
In the US you can report the spam texts by forwarding the message to 7726 (“SPAM” on your keypad) at which point your carrier will text you back and ask for the source number. This doesn’t report the message to the government agencies but just your carrier, so they can hopefully punish the platforms sending spam.
Use a site like https://www.freecarrierlookup.com/ to see which carrier or platform sent it, which is useful for the next step of reporting offenders.
Now report the incident at the FTC and FCC websites. Do this every single time so it eventually creates difficulties for the platforms enabling this. Mention the carrier or platform carrying the spam. Put in all the details correctly.
https://reportfraud.ftc.gov/
https://consumercomplaints.fcc.gov/hc/en-us/requests/new
If it is an iMessage you should use the built in “report junk” feature.
You can also go to the website of the platform that carried the message to report things through their abuse reporting pages, but not all of them are diligent. Some are happy taking money from spammers to abuse you, and will make you keep reporting each phone number that spams you because they do nothing about it except block that one number from contacting you. They won’t fix the underlying root cause of why they have all these illegal abusers as customers.
My personal experience is that the vast majority of text spam comes from a few offending text messaging platforms - for example Sinch (https://en.wikipedia.org/wiki/Sinch_AB) and Bandwidth (https://en.wikipedia.org/wiki/Bandwidth_Inc.) for example. These are potentially seemingly commercial platforms for spammers. Note that Sinch owns Mailgun and Mailjet too and has a long documented history of legal trouble due to spamming. Businesses should avoid using these platforms because their own reputation and delivery will be affected by being mixed with spammers.