Apr 28 2026
I pulled up our cloud bill last quarter and noticed a line item that did not exist two years ago, public IPv4 charges. AWS now bills $0.005 per public IPv4 address per hour, and across staging, production, and dev environments, those small charges added up fast.
That single line item forced a conversation more U.S. businesses are now having. Should you keep renting IPv4 from cloud providers, or should you acquire your own block and move it wherever you need it?
IPv4 scarcity is not new. The real change is cost pressure. Native IPv6 usage surpassed 50% of global Google service access on March 28, 2026, yet most business-critical dependencies, partner IP allowlists, email reputation, and legacy API callbacks still rely on IPv4. You cannot just skip it.
The hard part is not finding a block. The hard part is sizing it, proving need, checking reputation, and making it usable across cloud and on-prem networks without creating routing or email problems.
Use this as a working checklist before your first transfer.
The decision gets easier when you size the block correctly, understand transfer policy, and plan operations before you wire money.
You are buying control and registration rights, not physical property.
You are not purchasing real estate. You are acquiring the right to have IP number resources registered to your organization and routed under your ASN, or Autonomous System Number, under Regional Internet Registry policy.
U.S. buyers work mainly under ARIN, the American Registry for Internet Numbers. ARIN’s RDAP and Whois services provide the authoritative record of who holds a block. That registry data supports RPKI, the Resource Public Key Infrastructure, IRR route objects in the Internet Routing Registry, and the routing checks upstream providers use before they accept your announcements.
Think of it like a domain name. You control it as long as registration stays current and you follow policy. That distinction matters because it affects every step of the transfer, from pre-approval paperwork to post-transfer Route Origin Authorization, or ROA, publication.
Dedicated IPv4 still solves problems that IPv6 alone does not fix.
Even with IPv6 crossing the 50% usage mark, businesses still need stable IPv4 reachability for customer traffic, partner integrations, and cloud operations.
SaaS callback URLs, single sign-on integrations, partner IP allowlists, and legacy APIs still assume IPv4 endpoints. Dropping IPv4 reachability can break real workflows, delay onboarding, or force partners to rewrite systems they do not plan to touch this year.
AWS began charging $0.005 per public IPv4 address per hour on February 1, 2024. The EC2 Free Tier offsets 750 hours per month for the first 12 months, but after that, cost scales with every extra public address. Owning a block and using BYOIP turns part of that recurring expense into a one-time capital outlay with resale value.
Owning address space lets you warm sending IPs on your schedule, build a long-term sender reputation, and maintain clean reverse DNS, or rDNS. Shared cloud IPs can carry someone else’s spam history, and cleaning that up after launch is far harder than starting with known space.
Start with routing rules, then map the block to actual service demand.
Start at /24 and expand in powers of two as your needs grow. IPv4 routes more specific than /24 are commonly filtered on the public internet, which makes /24 the practical minimum for broad propagation and the floor for ARIN transfers.
A /24 gives you 256 addresses and fits a small SaaS edge, mail infrastructure, or a few public service pools. A /23 at 512 addresses fits an MSP running multi-tenant NAT with dedicated IP pools. A /22 at 1,024 addresses suits a regional ISP, WISP, or a business that wants room for cloud, mail, and disaster recovery without renumbering next year.
Count by public-facing use cases, not just by server count. Load balancers, failover pairs, NAT gateways, isolated environments, and clean mail IP pools all consume space. Keep growth contiguous when possible because aggregated announcements are easier to manage and less likely to trigger prefix-length filters downstream.
Treat IPv4 as a total-cost decision over 24 to 36 months.
Leasing can be cheaper across the first 12 months, and sometimes the first 24. Beyond that, asset value and control usually push the case toward buying. Re-architecting with dual-stack, plus NAT64 and 464XLAT where it fits, can reduce hard IPv4 demand, but it will not remove dependencies like email, partner allowlists, or third-party callbacks.
A mixed strategy is common. Lease for a short-term launch, buy for stable long-term pools, and re-architect internal services so future growth lands on IPv6 first.
Policy, not price alone, determines whether a transfer can close.
ARIN’s Number Resource Policy Manual governs U.S. transfers. Recipients must document at least 50% utilization within 24 months, and the minimum transfer size is a /24 under NRPM section 8.5. In practice, that means you need a clear deployment plan, not a vague claim that you might need space someday.
Source entities generally must not have received IPv4 from ARIN in the 12 months before transfer approval under NRPM 8.3 and 8.4, with limited exceptions for entities under common control. If the seller’s chain of title is messy, expect delays while ARIN verifies corporate history and authority to transfer.
Inter-RIR transfers under section 8.4 require approval from both registries, which adds time and paperwork. In the RIPE region, recipients of IPv4 by allocation or transfer cannot re-transfer the same space for 24 months. If you are buying RIPE-registered space through an inter-RIR transfer, you still need to pass ARIN’s needs test on the receiving side.
The safest source is the one that reduces title, compliance, and reputation risk.
If your team wants a managed transaction, it helps to compare brokers on escrow support, compliance checks, title review, contract handling, seller screening, and how much ARIN or RIPE paperwork they manage for you during the transfer. For U.S. SMBs that would rather keep internal staff focused on routing, cloud onboarding, and BYOIP setup instead of contracts and transfer coordination, you can buy IP addresses through a broker-led process.
You have three main channels, and each one trades price against process support.
A broker that supports escrow, seller screening, contracts, and ARIN transfer coordination can be useful when a small internal team needs to stay focused on routing, mail, and cloud onboarding instead of paperwork.
Bad space is expensive space, even when the purchase price looks attractive.
Verify ownership, routeability, and reputation before funds move. Skipping one of these checks can create problems that take weeks to unwind after closing.
Clean transfers move fastest when legal, finance, and network workstreams run in parallel.
Typical well-documented transfers close in two to three weeks, though inter-RIR cases or messy ownership histories can stretch that to four weeks or more.
Move quickly after closing so the block becomes useful before it becomes a target.
Make the space usable and safe before production cutover. Unannounced space that suddenly appears in your registry record can attract hijack attempts, and delayed mail or DNS setup can stall a launch.
BYOIP is where owned space starts paying back operationally.
BYOIP reduces recurring cloud IPv4 charges and gives you consistent addressing across environments. That consistency matters for customer allowlists, vendor callbacks, firewall rules, and disaster recovery plans that should not change every time you move workloads.
Across all three providers, your ROAs and IRR objects must reflect the cloud provider’s origin AS before onboarding. Reverse DNS delegation and PTR record setup also take longer than teams expect, so start those requests early.
Owned IPv4 is most valuable when you reserve it for the few places that truly need it.
Use dual-stack by default, then push new growth onto IPv6 wherever possible. NAT64, which lets IPv6-only clients reach IPv4 services, and 464XLAT, which translates traffic for mixed mobile and internal environments, can shrink your hard IPv4 requirement over time.
Move latency-tolerant public endpoints to IPv6-first behind a load balancer or CDN. Even if every customer is not ready, internal services and controlled partner links usually are. Track IPv6 user share each month so you know when you can reclaim IPv4 headroom, reassign clean pools, or eventually sell surplus space.
These are the questions that most often slow down an IPv4 purchase.
A /24, which provides 256 addresses. It is the minimum transfer size at ARIN and the de facto smallest prefix that propagates reliably because most operators filter anything more specific.
Clean, well-documented cases typically close in two to three weeks. Inter-RIR transfers and blocks with complicated ownership history can take four weeks or more.
Usually across the first 12 to 24 months. After that, owned space has residual resale value and removes ongoing lease payments, which can make a purchase more cost-effective for long-term use.
Yes, if you plan to announce the space directly through BGP. If not, an upstream provider can originate the prefix for you under a Letter of Authorization, though that gives you less routing control.
Yes. Publish ROAs before your first BGP announcement. Networks that enforce Route Origin Validation will drop invalid routes, and ROV adoption keeps growing across transit providers and large networks.
They turn public IPv4 into a recurring operating cost. BYOIP offsets part of that charge by letting you use owned space in cloud environments, and pairing it with IPv6 migration reduces exposure further.
Warm new sending IPs slowly, starting with low volumes to trusted recipients. Monitor Spamhaus and other blocklists daily during the first 30 days, and keep rDNS, SPF, DKIM, and DMARC correct from day one.
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