It does exist but you have to take the 5 minutes to fill out a form. You can find it at https://consumercomplaints.fcc.gov and click “Phone issues”. I also suggest simultaneously reporting to the FTC via https://reportfraud.ftc.gov/ and click “Report now”.

You can also forward spam text messages to 7726 in the US (goes to your cell phone carrier), which is very effective because the carriers have low tolerance for these issues and also train their own anti spam off this data.

I do submit a complaint for each instance. I’ve sent over a thousand now. Hopefully it’s useful data to someone.

My intent isn’t to reverse-spam the FCC though; the complaint form just only accepts one phone number at a time. Amusingly I’ve discovered that it’s possible to receive a higher volume of spam than the FCC’s rate limits allow reporting.