A U.S. SaaS CFO opens the February 2024 AWS bill and sees a new charge for every public IPv4 address. Engineering replies that rotating those addresses would break customer allowlists, which are approved source IP lists, and weaken email deliverability.
That charge is not a billing error. It is a clear signal that public IPv4 is now a metered, finite asset.
ARIN, the American Registry for Internet Numbers, exhausted its IPv4 free pool on September 24, 2015. Since then, addresses have moved through a secondary market at prices in the mid-$20s per IP. AWS began charging $0.005 per hour for each in-use public IPv4 address on February 1, 2024, and Google Cloud prices standard external IPv4 at about the same rate.
For teams that run customer-facing services, payment flows, or fixed partner allowlists, IPv4 now deserves the same planning discipline as compute, storage, and security.
Key Takeaways
- IPv4 charges signal its status as a limited asset, impacting costs and uptime for businesses.
- Planning for IPv4 now can control costs, improve reliability, and ensure routing autonomy.
- Businesses should consider purchasing IPv4 addresses as a long-term infrastructure decision instead of relying on leasing.
- Clean IPv4 acquisition involves careful vetting, proper paperwork, and understanding transfer processes to avoid issues.
- Owning IPv4 remains essential as critical services still rely on it, despite the growing adoption of IPv6.
Table of contents
Why IPv4 Scarcity Is a Business Issue
IPv4 is no longer cheap plumbing, it is a constrained input that affects cost, uptime, and risk.
IPv4 tops out at roughly 4.3 billion addresses. Regional Internet Registries, including ARIN, RIPE, and APNIC, handled the original allocations, but the easy supply is gone.
Today, businesses get addresses through specified transfers, inter-registry transfers, brokers, or direct market deals. Those blocks are then routed through an ISP or used in Bring Your Own IP, or BYOIP, programs in the public cloud.
Google’s measurements showed IPv6 traffic briefly passed 50% on March 28, 2026. That progress matters, but enterprise APIs, payment gateways, email systems, and legacy security tools still rely on stable IPv4 endpoints.
Three Reasons to Plan for IPv4 Now
Early planning turns IPv4 from an emergency purchase into a controlled infrastructure decision.
Cost Control Versus Cloud IP Fees
At $0.005 per hour, one always-on public IPv4 costs about $43.80 per year. A fully used /24, which contains 256 addresses, can cost more than $11,200 per year in provider fees alone. If market pricing for a clean /24 sits around $6,400 to $9,000, heavy use can justify ownership within a year.
Reliability for Allowlists and Reputation
Owned space reduces churn for customer allowlists, vendor firewalls, and fraud controls. It also lowers the chance of landing on recycled provider IPs that carry old blocklist history from earlier tenants.
Security and Routing Autonomy
Ownership also improves routing control. Resource Public Key Infrastructure, or RPKI, lets you create Route Origin Authorizations, or ROAs, that tell the internet which network may announce your prefix through Border Gateway Protocol, or BGP. That helps prevent route leaks and hijacks, and it gives security teams cleaner incident data.
What to Buy for Clean Scaling
Most businesses should start with the smallest block that cloud routing and real demand will support.
A /24 is the practical minimum because it is the smallest prefix most networks route globally, and it meets BYOIP requirements across AWS, Azure, and Google Cloud. Go larger only when finance and network data show you can use the space within 24 months.
If you need a clean /24 for a near-term migration, specialist marketplaces can help coordinate escrow, letters of authorization, and transfer paperwork.
Check these items before money moves:
- WHOIS ownership, org records, and contacts match the seller.
- Chain of custody is documented from the current holder back to prior transfers.
- Spamhaus, Talos, and passive DNS data show no material abuse history.
- No active BGP announcements remain under the seller’s control.
- Geolocation databases are reviewed for major mismatches.
- A post-transfer plan exists for ROAs, monitoring, and cloud commissioning.
After you finish that vetting checklist and confirm the seller, abuse history, transfer path, and post-transfer controls all line up, it makes sense to compare marketplaces that can support ARIN 8.3 documentation, LOA coordination, blacklist checks, and closing logistics before your planned cloud cutover, and one practical next step is to buy IP addresses through a marketplace built for that process.
How to Buy and Stay Compliant
Good paperwork matters as much as price when you acquire IPv4 space.
In the ARIN region, Section 8.3 covers transfers to a specified recipient, and Section 8.4 covers inter-registry transfers. ARIN also offers pre-approval based on a 24-month need forecast, which can shorten closing time and reduce last-minute document problems.
Do not judge a broker on price alone. Ask about completed transfers, escrow handling, letters of authorization, blocklist remediation, and support for WHOIS and RPKI updates. A cheap block with a bad history can cost more than a clean one.
Before you announce the space in the cloud, confirm each provider’s commissioning steps and minimum prefix rules. A disciplined cloud migration process keeps cutover predictable; stagger announcements, set ROAs for the authorized origin networks, and watch routing tables closely so you do not create avoidable reachability issues.
One common objection is that leasing feels safer because it avoids upfront spend. That can be true for short tests or bursty projects, but persistent egress, email, and allowlisted partner traffic usually favor ownership once recurring cloud fees and migration friction are counted.
How to Measure IPv4 ROI
Success shows up in finance, routing health, and daily operations.
On the finance side, track payback period, avoided provider IP fees, transfer costs, and the time needed to commission the block. Compare those figures against conservative utilization so the business case holds under normal demand.
On the network side, monitor ROA coverage, abuse reports, blocklist status, and availability after BYOIP cutover. Stable latency and clean reputation matter because a cheap block loses value fast if customers cannot reach you or your mail is throttled.
On the operations side, measure transfer lead time, change success rate, and the number of allowlist tickets avoided after moving to owned space. Those metrics translate technical work into language finance leaders understand.
Make Scarcity Work for You
The best strategy is dual-track: buy only the clean IPv4 you need now, while accelerating IPv6 to lower future pressure.
There is no advantage in panic-buying space you cannot use. There is a real advantage in disciplined sizing, clean provenance, and tight routing controls that let you move the same addresses across clouds as your footprint changes.
That approach also helps security teams. When address ownership, ROAs, monitoring, and incident playbooks stay aligned, investigations move faster and customer-facing changes create less churn.
Common Questions
A few practical questions come up in almost every IPv4 purchase review.
How Long Do ARIN Transfers Take?
With pre-approval and a responsive seller, think in weeks, not months. Inter-registry deals and missing documents can extend that timeline.
Should You Lease or Buy?
Lease for short-lived projects, pilots, or temporary capacity. Buy when the addresses support persistent workloads, partner allowlists, or email reputation that you do not want to reset.
If IPv6 Has Passed 50%, Why Still Own IPv4?
Because critical business traffic still lands on IPv4. Legacy partner networks, payment tools, anti-fraud controls, and email infrastructure are not migrating at the same speed.
