Xfinity IP Address is on Spamhaus Blacklist. How to remove off the blacklist?

... My IP Address has always been on the blacklist ever since signing up with Xfinity. ...

Which list is it on? If you are a residential Comcast customer and asking about your public IP, you can't remove it from the Policy BlockList ("PBL"). All residential IPs are dynamic and are, or should be, on the Spamhaus and a bunch of other policy blocklists.

A blocklist entry doesn't mean you can't send email, it only means you can't operate an email server on your Comcast Internet service.

Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.

It's true what @BruceW says.  Generally, everyone running legit email servers will block ISP dhcp pools from cable/dsl consumer providers regardless if the ISP 'unblocks' a port for you so you can run your own mail server.  You'll be able to receive mail, but you'll run into rejections sending.

I honestly believe every machine on wandoo.fr has been hijacked since the 90's as an example.  Comcast used to be exceptionally bad before their port 25 residential  block due to all the end user poorly configured open relays.  We were all rejecting everything on every IP pool the company owned, business accounts included.  That still happens on business accounts frequently on their network due to their lack of over-site and failure to respond to 'abuse' to this day.

What this really comes down to is the reporting to the DNSBL/RBL and automated reporting by clients plus our own mail servers.  You get enough hijacked spam bot machines in the assigned subnet, the entire CDIR range in your current pool ends up blocked by IP address automatically, and they aren't using your FQDN.  Nobody cares about your domain name or your SPF record, or your DKIM signature as those are always spoofed and created on the fly by spammers anyway and change all the time, but we do know which network it came from.  When you want to check a multi-RBL, use the IP address and not your domain name to see how many lists you are on.  Your IP address will also change from time to time, then you'll hit the same issue with the next pool you get assigned to, even if you could get a list to unblock you.

It's really important to research hosting companies if you are going to move to one of those for your mail server.  Colorado Crossing, Eonix, and even SalesForce as of late have been horrid and have extremely poor reputations going for them.  Personally, I don't care what any of their customers want to send me, it's all spam.  If you're going to lease rack space or run a VPS, you're going to want to do your own homework on the hosting company or you'll find yourself in the same boat.  It only takes a few compromised machines, and inaction by the provider to murder a reputation.  If you are using a legit hosting company, you have a chance at unblocking RBL lists.  I wouldn't hold out too much hope for Xfinity's network though.  We generally just laugh at removal requests for my gear.

If you'd like to DM me your IP, I can take a look.  The other two responses are within reason.  If the IP in on the PBL, that is by design as Residential IPs are deemed dynamic.  If this is a commercial IP, that's a different question.  If the IP is on a different RBL, we can also take a look.  Thanks