TalkTalk are a completely awful ISP. Not sure what the US equivalent would be, but they're the kind who do promotions of "Broadband for £3/month"-level. You get what you pay for service-wise, but they are also by far the most enthusiastic ISP around when it comes to censorship; they have a spider that follows their users to all URLs they visit to categorise the sites[1] (giving them the nickname StalkStalk), and have been doing this long before the current set of idiots in Parliament forced censorship in (at least since 2011).

I'm in a similar situation, one site I run is blocked both by StalkStalk and BT. No porn, no other 'adult' content; it's deliberately kept PG-13 to use the US ratings.

[1]Check your logs for HuaweiSymantecSpider. It obeys robots.txt though, so a quick "Disallow: /" in robots.txt stops it, although they still grab content from unencrypted pages via DPI.

No HuaweiSymantecSpider in my logs in the past 8 months (grepped access.log), but the site is available over both http and https so they might have classified it using DPI (talk about evil...).

My geek blog and a couple of other similar ones are also blocked by TalkTalk. It seems to be a bulk problem. I have emailed them asking for an explanation.

One talk-talk subscriber has reported that he can see these blogs just fine. Though he does not have the "kid safe" setting turned on, of course. "Blocked" in this context probably means "blocked when using the most restrictive settings".

TalkTalk has more than one filter setting.

Ask them if your site is blocked at the "Kid Safe" level (the default) which is what the probes run on.

BT is blocking my site about my homebrewed beer. That's fun.