Last quarter, our outreach team hit a wall. Shared-pool IPs were landing in spam folders, regional traffic was pinned to the wrong state, and a vendor’s recycled block triggered a client firewall during a critical crawl window.
We needed our own IPv4 space. Buying it felt less like ordering a server and more like closing on commercial real estate, with title checks, escrow, and registry filings.
That experience is common. IANA’s remaining IPv4 space was fully distributed in early 2011 when the final five /8 blocks went to the RIRs. ARIN announced depletion of its own free pool on September 24, 2015. RIPE NCC exhausted its available pool in November 2019 and moved to a waiting-list model.
Today, buyers enter a secondary market with real money, real fraud risk, and policy gates that can slow a deal for weeks or months.
A safe purchase starts with sizing the block, then moves through due diligence, escrow, registry approval, and a careful rollout plan.
Key Takeaways
These points shape cost, timing, and operational risk in every IPv4 deal.
- Buying IPv4 is not just budget, it is policy. ARIN asks recipients to show at least 50% use of the requested block within 24 months, so get pre-approval before you shop.
- A /24 is the smallest unit that will reliably route across the global default-free zone. This zone is the shared routing table used by major internet carriers, and smaller prefixes may not propagate end to end.
- Reputation drives value. Check Spamhaus DROP, major email reputation systems, and historic abuse records before you wire funds.
- Secure routing on day one. Publish route origin authorizations (ROAs), under RPKI, the framework described in RFC 6482, then update Internet Routing Registry records right away.
- Geolocation affects user experience and reporting. Publish an RFC 8805 geofeed and reference it per RFC 9632 so providers can pull corrections.
- For SEO, a unique IP does not create a ranking boost. Google’s John Mueller has repeatedly said shared IPs are fine, so focus on deliverability, stability, and operations.
Evaluation Criteria For IPv4 Address Space
Understand IPv4 Transfers
An IPv4 purchase is a registry-controlled transfer of authority, not a normal retail transaction.
You are not buying land or a perpetual property deed. You are becoming the registered holder of a number resource under a Regional Internet Registry(RIR) agreement.
The main RIRs are ARIN for North America, RIPE NCC for Europe and the Middle East, and APNIC for Asia-Pacific. Transfers usually happen either between unrelated parties or as part of a merger or acquisition. ARIN’s Section 8.3 and 8.4 policies cover those paths, and the minimum transfer size is a /24.
After approval, the record has to move in the Registration Data Access Protocol(RDAP), which replaced older Whois lookups for number resources. The holder name, contacts, and abuse points of contact should match the deal paperwork before you announce anything.
The operational step comes next. Border Gateway Protocol (BGP), is the system networks use to tell the internet where your addresses live, so your registry record and your routing plan need to line up.
Compare Buying, Leasing, and Alternatives
Buy when the addresses become part of your long-term network, and lease when the need is short and narrow.
Buying makes sense when you need stable control, a lasting reputation profile, and the option to route the block through your own autonomous system. That fits multi-region sites, permanent mail systems, crawl or proxy fleets, and bring-your-own-IP deployments in cloud platforms.
Leasing fits short campaigns, test windows, and cases where capital is tight. Monthly rates are lower up front, but two or three years of rent can erase that advantage fast.
Alternatives exist, but each has tradeoffs. NAT64 lets IPv6-only systems reach IPv4 services through translation. Carrier-grade NAT(CGNAT), lets many users share one public IPv4 address. Provider-assigned space removes the transfer burden, but it also limits portability and can complicate mail and crawl consistency. Google’s public statistics show global IPv6 usage regularly near 45 to 50%, with a reported brief peak around 50% of Google traffic on March 28, 2026.
If you only need a few clean outbound IPs for one quarter, buying may be overkill. If the address space will sit inside your architecture for years, ownership is usually easier to defend.
Plan Your Allocation and Get Pre-Approval
Right-sizing the block before you negotiate saves money and keeps the transfer review focused.
Start with the smallest block that meets growth and routing needs. For most mid-market teams, that is a /24, which gives you 256 addresses. A /23 or /22 can make sense if you expect steady growth, multiple environments, or separate routing policies. Inside the block, reserve slices for mail, web, VPN, and spare capacity instead of treating the whole range as one pool.
For U.S.-based teams, ARIN pre-approval removes a major risk. Submit a utilization plan that shows 50% use within 24 months, include subnet plans, network diagrams, and your ASN details, and leave room for follow-up questions. Vague narratives and missing growth assumptions are common reasons tickets stall.
Teams working in RIPE NCC or APNIC regions should still verify recipient requirements before price talks go too far. Policies differ, and a seller’s clean paperwork does not guarantee your side is ready.
One practical test helps. Map the first year of use on paper. If you cannot show where the first 100 to 130 addresses will go, you probably have not sized the deal well enough.
Source IPv4 Safely
The safest source is the one that can prove ownership, history, and a clean transfer path before money moves.
Most buyers use one of three paths: a qualified facilitator, a dedicated marketplace, or a direct private sale through industry contacts. ARIN retired its Specified Transfer Listing Service on June 1, 2023, so buyers now rely more on its Qualified Facilitator Program and private marketplaces. Each path can work, but only if the seller is the documented RIR holder and agrees to escrow.
A clean listing has an accurate RDAP record, a clear transfer history, current routing objects, and no signs of liens or disputes. Red flags include mismatched netnames, stale customer assignment records, old abuse contacts, or a seller who pushes for direct payment outside escrow.
Teams that want a structured process can compare listings, documentation, and transfer support through a vetted marketplace. This kind of marketplace helps when you already have pre-approval and want pricing visibility, the chance to review clean /24s before escrow, and transfer tracking in one place instead of a loose email chain, and buyers who need that clarity often start by using Buy IPv4.
Even then, do your own checks. Ask for proof of control, the last transfer date, any past abuse complaints, and the exact steps that trigger escrow release. A marketplace speeds paperwork, but it does not replace judgment.
Check Reputation and Hygiene
A block that looks cheap on paper can become expensive fast if its history is dirty.
Start with blocklist and reputation checks. Query the range against Spamhaus DROP and SBL/XBL, Barracuda’s reputation system, and Cisco Talos. Spamhaus DROP entries are meant to be blocked at the network edge, so a hit there is a strong reason to walk away. Talos also matters because several mail security products use its IP reputation data as one input.
Next, review passive DNS and historic routing. Tools such as RIPEstat BGPlay and Hurricane Electric’s BGP Toolkit can show route changes, past origin ASNs, and odd periods when the same prefix appeared from several networks. Those patterns can point to hijacks, sloppy operations, or abuse.
Use a simple scorecard. Pass means clean across all checks. Review means minor flags with clear supporting documents. Fail means active blocklist entries, unresolved hijack history, or evidence of malware, botnets, or bulk spam.
Ask one more question before signing. Did the block recently carry mail, proxy, or scraper traffic? A quiet range can still inherit a bad neighborhood if it spent years inside a larger dirty allocation.
Protect the Deal With Legal Terms and Escrow
Good legal terms and controlled fund release protect you from problems that technical checks cannot catch.
Use an asset purchase agreement with clear warranties. The seller should confirm identity, authority to transfer, clean title, and the absence of liens or other claims. KYB verification should be completed to confirm the legitimacy of all involved legal entities. Add indemnities for pre-transfer abuse and a written obligation to cooperate with the RIR until completion.
Funds should move through regulated escrow tied to RIR milestones. A common structure is simple: escrow receives the funds at signing, holds them while both parties complete registry steps, then releases payment only after the RIR approves the transfer and the RDAP record reflects the new holder. For inter-RIR deals, bring counsel in early because sanctions screening, KYC checks, and dual-registry coordination add time.
Before you close, confirm the receiving organization name, legal entity details, billing contacts, and ASN information match across the contract, escrow file, and RIR ticket. Small mismatches create outsized delays.
Execute the Transfer and Harden the Block
A clean transfer still fails operationally if routing, geolocation, and mail setup lag behind the registry update.
Sync the RIR ticket, routing data, and upstream providers before the cutover window. For ARIN, both source and recipient open tickets, sign the Registration Services Agreement, and pay required fees. Once the record updates, publish ROAs for your origin ASN, add Internet Routing Registry route objects, and confirm route origin validation shows a valid state before announcement.
Coordinate with upstreams early. Send Letters of Authorization, check that prefix filters will accept the new block, and use staged BGP communities if your carriers support them. A shared checklist keeps the network operations team aligned.
Fix geolocation right away. A geofeed is a simple file that maps IP ranges to location data. Publish one under RFC 8805, reference it in your registry object per RFC 9632, and submit manual corrections to providers such as Google, Cloudflare, MaxMind, and IP2Location.
If you will send email, warm the space slowly. Ramp volume over two to four weeks, set reverse DNS before first send, and confirm SPF, DKIM, and DMARC are live. Register for ISP feedback loops and watch seed tests, bounce rates, complaints, and reputation dashboards every day during the ramp.
Your day-one monitor set should cover blocklists, route leaks, hijack alerts, registration drift, and ROA validity. When something trips, the response path should already be written, with owners and time targets.
Budget for the Full Cost
The purchase price is only one line item in the real cost of IPv4 ownership.
Industry pricing reports suggest IPv4 prices peaked around $50 per IP in 2021 and settled into the low-$30s per IP across many block sizes by late 2024 through 2025. Smaller blocks, especially /24s, usually carry a per-IP premium.
Model the total cost of ownership, not just the transfer price. Add RIR fees, escrow charges, legal review, engineering time, migration work, and the ongoing cost of monitoring and reputation management. Compared against 24 to 36 months of leasing, ownership usually wins when you expect to hold the space for five years or more.
Know What Matters for SEO
IPv4 ownership helps SEO through reliability, not through a direct ranking signal.
Owning IPv4 will not boost rankings by itself. Google’s John Mueller has repeatedly said that dedicated IPs do not offer inherent ranking advantages. The practical value is cleaner deliverability for outreach mail, more stable geolocation, and consistent endpoints across clouds and CDNs.
The indirect SEO gains come from fewer operational failures. A mis-geolocated block can skew regional reporting. A blocklisted range can sink outreach without obvious errors. Unstable routing can make pages intermittently unreachable for crawlers.
Avoid migration damage by not changing IPs, hosting, CDN behavior, TLS settings, and URLs at the same time. Test crawlability after the move, update sitemaps if needed, and watch server logs and Search Console crawl data for at least 30 days.
Measure Success
Success is visible when deliverability, routing, and reporting all stay stable after the cutover.
Track the results you can control. For mail, watch inbox placement, bounce and complaint rates, reverse DNS accuracy, and reputation dashboards such as Talos and Barracuda. For network health, monitor path stability, ROA status, and leak or hijack alerts.
For web and SEO, review Google Search Console crawl stats, segment server logs by source and destination IP, and compare regional latency and geolocation accuracy before and after the move. Set clear incident triggers, such as a new blocklist hit or a sharp crawl drop, so response starts within hours, not days.
FAQ
Most transfer problems come from sizing mistakes, weak documentation, or poor post-transfer operations.
Do I Need a /24?
For global propagation, plan on a /24. It is the smallest prefix that will reliably move across the default-free zone, so anything smaller may disappear from parts of the internet.
Is Buying IPv4 Legal?
Yes, when the transfer follows the relevant RIR policy. Use a proper contract, regulated escrow, and the official registry process so your control of the resource is documented.
How Long Does a Transfer Take?
Timing depends on the registry and the quality of your paperwork. Intra-ARIN transfers with pre-approval and clean documents can close in two to four weeks, while inter-RIR deals usually take longer because two registries must coordinate.
Will a Clean Block Stay Clean?
Not on its own. Publish ROAs, separate mail from web traffic, monitor blocklists continuously, and answer abuse reports fast. Reputation decays quickly when a range is neglected.
What About IPv6?
Run dual-stack where you can. IPv6 usage is nearing parity in some views of global traffic, but IPv4 still matters for legacy partners, mail flows, and third-party tools that have not finished the transition.
What Breaks SEO During an IP Migration?
The IP change itself is rarely the root problem. Trouble starts when teams also change hosting, CDN rules, TLS, firewalls, or URLs at the same time, or when new WAF rules block Googlebot. Stage the move and verify crawl access in logs.
