Static residential proxies, also sold as ISP proxies, are IP addresses registered to consumer internet providers but hosted on a proxy provider's servers in a data center. The address looks residential in registry and routing data, while the hardware behind it has datacenter uptime and bandwidth, and the address stays assigned to you until you release it. They suit long sessions, allowlisting and account continuity; they are the wrong tool when you need millions of distinct addresses or fine-grained location spread.
This guide goes further than our comparison of residential, ISP and datacenter proxies: how the addresses are obtained, why targets classify them the way they do, how to check the subnet spread of what you are sold, how to confirm the addresses really are ISP-registered, and what to ask about replacement and billing.
What are static residential proxies?
A static residential proxy has three properties that are usually found apart.
- The address block is registered to a consumer ISP. A registry lookup names a broadband or cable provider as the holder, not a hosting company.
- The address is announced by that ISP or with its authorization. Routing data shows the traffic originating from an autonomous system (ASN) that belongs to, or is authorized by, the ISP.
- The server is not in anyone's home. The provider leases the addresses from the ISP and terminates them on its own hardware, typically in a colocation facility with direct upstream connectivity.
The commercial arrangement is a lease: the ISP allocates a range to the proxy provider, and either announces it from its own network toward the provider's equipment or authorizes the provider to announce it. Nothing about the address changes from one day to the next, which is where "static" comes from.
The two names describe the same product from different angles. "ISP proxies" describes the registry owner. "Static residential" describes how the address is classified by targets. Some vendors also use "static residential" for long-held sessions on real household devices; that is a different product with different uptime characteristics, so ask which one you are being offered.
Why do targets treat ISP addresses as residential?
Most targets do not inspect the physical device behind an address. They classify it from data they can get cheaply:
- Registry data. Who holds the range, according to the regional internet registry.
- Routing data. Which ASN announces the prefix, and what kind of network that ASN is.
- Commercial IP-intelligence databases. Vendors that label ranges as residential, mobile, hosting or business, largely derived from the first two plus observed behavior.
- The target's own history. How much abuse it has seen from the range and the specific address.
An ISP-leased address passes the first three: the holder is a consumer ISP, the announcing network is an access provider, and intelligence databases tend to label it residential. That is the whole trick, and it is also the limit. The fourth signal is behavioral. An address that sends thousands of requests an hour to one site, from one device fingerprint, around the clock, is not behaving like a household, and a target that watches per-address volume will rate-limit it regardless of what the registry says.
Some intelligence vendors have also started flagging ranges known to be leased to proxy providers. Classification is not permanent, so treat "passes as residential" as something you measure against each target, not a property you buy once.
When static residential proxies beat rotating residential
Rotating residential proxies route through real household devices, so the address you get depends on which peers are online. Static residential proxies trade that breadth for stability. They win in five situations.
- Long sessions. A logged-in workflow that must keep one address for hours or days. A residential sticky session ends when the peer's device goes offline; an ISP address does not, as our guide to rotating vs sticky proxies explains.
- Allowlisting. When a partner, a customer's API or your own firewall must allowlist your egress addresses, you need addresses that do not change. Nothing that rotates can be allowlisted.
- Account continuity. Platforms that tie risk scoring to login location react badly to one account appearing from a new address on every session. One account per static address, held for months, looks like one customer at home.
- Throughput and latency. The server behind an ISP address has datacenter uplinks, so large responses, file downloads and latency-sensitive calls run at speeds a household connection cannot match.
- Predictable cost. Billing is per address per month, so a high-bandwidth workload costs the same whether it moves one gigabyte or a thousand.
When they are the wrong choice
The same properties make static residential proxies a poor fit elsewhere.
- You need many distinct addresses. A workload that must spread load across hundreds of thousands of addresses to stay under per-address limits needs a rotating pool. Buying that many static addresses is uneconomic and usually impossible.
- You need city-level or broad geographic spread. ISP addresses exist where the provider has leased ranges, and they geolocate wherever the ISP registered them. A rotating residential pool covers far more locations.
- Your request rate per address is high against a strict target. Static addresses accumulate reputation. If a target blocks one, it stays blocked until the provider replaces it.
- Your volume is low and bursty. A job that runs a few hundred requests a week may cost less per GB on a rotating pool than per address per month.
A useful rule: if the workload needs the same address to persist, choose static; if it needs many addresses to look independent, choose rotating. Many estates run both, per workload.
Subnet diversity: why /24 spread matters
When a provider allocates you fifty ISP addresses, where they sit in the address space matters as much as how many there are. Targets and intelligence vendors often apply reputation and rate limits at the level of a /24 (256 addresses), and sometimes at the level of the whole announced prefix. Fifty addresses in one /24 can be throttled or blocked as a group; fifty addresses spread across twenty /24s from several ISPs cannot.
Ask for three things before you buy:
- the number of distinct /24s your allocation will span;
- the number of distinct ISPs and ASNs behind it;
- whether you can request a spread when ordering, or only receive whatever is free.
Then check what you receive. Given the list of addresses from your dashboard or API, a few lines of Python count the spread:
import ipaddress
import sys
from collections import Counter
addresses = [line.strip() for line in sys.stdin if line.strip()]
subnets = Counter(
ipaddress.ip_network(f"{a}/24", strict=False) for a in addresses
)
print(f"{len(addresses)} addresses across {len(subnets)} /24 subnets")
for subnet, count in subnets.most_common(5):
print(f" {subnet}: {count}")
A spread of one or two /24s for a large allocation is a finding to raise with the vendor before you build on it.
How to verify an address is really ISP-registered
"ISP" on an invoice is a claim, and the evidence for it is public. For a sample of the addresses you are allocated, check who holds the range and who announces it. Registration data comes from the registries' RDAP services, specified in RFC 9082; ARIN's endpoint redirects to the right regional registry for addresses it does not hold. Routing origin comes from public routing data such as RIPEstat:
IP=203.0.113.10
curl -sL "https://rdap.arin.net/registry/ip/$IP" \
| jq '{handle, name, type, country, startAddress, endAddress}'
curl -s "https://stat.ripe.net/data/network-info/data.json?resource=$IP" \
| jq '.data'
curl -sL "https://rdap.arin.net/registry/autnum/ASN_FROM_ABOVE" \
| jq '{handle, name}'
What you want to see: the range registered to a consumer ISP, announced from an ASN belonging to that ISP or explicitly authorized by it, and the address resolving to the country the vendor sold you. What should prompt questions: the range registered to a hosting company or to the proxy provider itself (that is a datacenter address, whatever the label says), a holder you cannot identify, or an announcing ASN unrelated to the registered holder with no explanation.
The lookup proves the address is ISP-registered. It does not prove the lease is legitimate. For that, ask for the commercial relationship: which ISPs the provider leases from, under what agreement, and whether the ranges are covered by the provider's sourcing audit. Our method for verifying a proxy provider's IP sourcing covers the documents to request and how to trace a sample.
Replacement policy and billing
Two contract questions separate a usable ISP product from a frustrating one.
Replacement
Static addresses can go bad: a target blocks one, an intelligence vendor relabels a range, or an ISP reclaims a lease. Ask, and get in writing:
- Under what conditions will the provider replace an address at your request, and how many times per billing period?
- How quickly is a replacement issued?
- Will the replacement come from a different /24, or the same one?
- How much notice do you get when the provider replaces an address on its own initiative, for example when a lease ends?
- If you have allowlisted an address with a partner, is there a way to keep it through a dispute?
The fourth question matters most for allowlisting. A partner firewall rule pointing at an address that silently changed is an outage you learn about from the partner.
Billing
ISP proxies are billed per address per month, not per gigabyte. Check whether the month is a calendar month or a rolling period from the order date, whether unused days are credited when you release an address early, whether bandwidth is genuinely unmetered or subject to a fair-use cap, and whether a paid trial lets you test a handful of addresses against your own targets before committing. Our guide to proxy pricing per GB and per IP shows how to compare the two models for a given workload.
Exclusivity
Finally, ask whether each address is exclusive to you for the whole period and what it was used for before. A previously abused address carries its history into your workload. The questions to ask are the same as for any dedicated vs shared proxies decision.
Static residential proxies at ProxyForge
ProxyForge ISP proxies are static addresses leased from consumer ISPs, hosted on our hardware and dedicated to one customer. Each supports HTTP, HTTPS and SOCKS5, with username and password or IP allowlist authentication, and they are billed per address per month from a prepaid wallet with no monthly minimum. A paid trial lets you test a small allocation against your own targets first; current rates are on the ISP pricing page.
Direct ISP leases are one of the permitted channels named in our public supply-chain policy; the sourcing page sets out that policy and the twice-yearly independent sourcing audit. The RDAP checks above work on our addresses as on anyone's; we would rather you run them than take the label on trust.