What a residential proxy actually is
A residential proxy routes your traffic through a real household IP address, assigned by an actual ISP to an actual home connection, and BirdProxies bills it by bandwidth (currently around 2.25-3.50 EUR per GB depending on plan size), not by the IP. You don't buy a fixed IP. You get access to a pool of real-user IPs, and every request (or every session, if you use a sticky session ID) can come from a different one. That's the entire value proposition: to the site you're hitting, your traffic looks like normal residential internet users because it is. This is why residential proxies are the default answer for scraping sites that fingerprint by ASN and IP reputation, for spreading account creation across many distinct-looking users, and for anything where you genuinely want a fresh identity per request or per session.
What an ISP proxy actually is
An ISP proxy is a static IP that's datacenter-hosted but registered to an ISP block, so it carries residential-style trust while staying put. BirdProxies bills it per IP per month (roughly 1.40-2 EUR/IP) rather than by bandwidth, with a 10-IP minimum on ISP orders. You buy the IP and it's yours for the billing period. It doesn't rotate unless you swap it yourself. That permanence is the whole point: one account, one IP, indefinitely, with no per-GB counter running while a page loads its images and scripts. Because the hosting itself is datacenter infrastructure, latency tends to be lower and more consistent than a residential connection sitting in someone's home, which matters when speed at checkout or during a page load is part of the job.
The Meta Ads scenario: when one stable identity beats a rotating pool
If you're setting up a long-lived Meta Ads account (the r/proxies thread from a poster new to proxies, planning to run a Business Suite profile "long term" for pixels, pages, and media uploads, no scraping, just normal ad operations) the case for a static IP is straightforward. Ad platforms read IP changes as a signal. An account that logs in from a different IP every session looks more like it's been compromised or handed off than one that quietly logs in from the same address every day. Residential proxies are built to rotate; that's a feature for scraping and a liability for an account you want to age and keep clean for months. An ISP proxy held on that one profile removes the variable entirely: the account sees the same IP at signup, at daily login, and a year later. If the goal is one identity kept alive indefinitely, that's a static-IP problem, not a rotating-pool problem.
The scraping-cost scenario: when rotating residential gets expensive fast
The other real thread here (someone reworking a scraping setup, rotating residential working fine for success rate but "paying per GB gets expensive pretty quickly" once the target sites are image-heavy or loaded with JS) describes the actual failure mode of per-GB billing: a heavy page can be many times the payload of a lean API response, and every image, script, and font that loads counts against your GB meter even though none of it is the data you actually wanted. Rotating residential still wins on IP diversity and success rate against aggressive anti-bot systems. But the targets don't always need a fresh IP on every single request. If you're hitting the same handful of sites with a small set of accounts or sessions, not evading detection at scale, paying per IP with static ISP proxies instead of per GB can flatten a bill that grows every time a page gets heavier. The fix usually isn't abandoning residential. It's not paying bandwidth rates for traffic that doesn't need to rotate.
A privacy note worth separating from the residential-vs-ISP question
A separate but related question came up in the r/proxies threads too: whether a proxy operator (residential, ISP, or otherwise) can see the exact URL you're visiting, not just the domain. The honest answer doesn't depend on which proxy type you use. It depends on the connection. Over plain HTTP, a proxy in the middle can see the full path and query string. Over HTTPS, which is what nearly everything now uses, a standard forward proxy only sees the destination host via the CONNECT request and the TLS handshake's SNI field. It cannot read the specific page path or the page content, because that's encrypted end to end. That's true whether the IP behind the proxy is a residential household connection or a static ISP-registered address. The proxy type changes how you look to the destination site. It doesn't change what a proxy can see in the middle of an HTTPS session.
A decision framework you can actually use
Pick residential when you need IP diversity at request or session level, when you're creating or warming many accounts and want each to look like a distinct real user, or when you're scraping targets with aggressive IP-reputation defenses where getting flagged is the real risk. Pick ISP when you need one account to sit on one identity for a long time, when the job is a fixed set of accounts or sessions rather than an expanding pool of identities, or when a per-GB bill is climbing on heavy pages and the target doesn't actually require rotation to succeed. It's fine to run both at once for the same operation: use residential to create and warm an account through its early, most scrutinized days, then move it onto a static ISP IP once it's established and just needs to stay put. That's not a compromise. It's matching the billing model and the rotation behavior to what the account actually needs at that stage of its life.