If your apps, email servers, or customer portals still need direct IPv4 reachability, the pressure is real. Free public pools are gone, and heavy Network Address Translation, or NAT, adds cost and complexity.
The secondary market gives you a practical way to add space when leasing feels risky or too expensive. If you plan carefully and follow policy, the process is structured, legal, and manageable.
What Matters Most
A clean transfer starts with planning, proof, and careful follow-through.
- Transfers are legitimate when they follow the Regional Internet Registry rules. In ARIN, recipients usually need to show 24 months of justified use, and the smallest transferable block is a /24.
- Due diligence protects your reputation. Check registry records, blacklist status, and routing history before you agree to terms.
- The real cost goes beyond the per-IP price. Budget for escrow, registry fees, broker fees if you use one, and the engineering work needed to turn the block up.
- Post-transfer setup matters as much as the deal itself. Routing records, reverse DNS, geolocation data, and security controls need attention right away.
Understand the Transfer Market
You can acquire IPv4 space legally through the Regional Internet Registry transfer rules.
ARIN, the American Registry for Internet Numbers, exhausted its free IPv4 pool on September 24, 2015. RIPE NCC ran out of general-use space around the same period, which pushed demand into the transfer market.
Most business transactions are recorded by a Regional Internet Registry, or RIR, after both sides meet policy requirements. In ARIN, that usually means section 8.3 for in-region transfers and 8.4 for inter-RIR transfers, with a minimum size of /24 and proof of need for the next 24 months.
Why Ownership Still Matters
Owning your own block gives you control that a short lease cannot match.
Control and Stability
Your public space stays with you, not with a lessor that can change terms or end service. That matters for long-lived DNS records, reverse DNS, partner allow-lists, and any system that is painful to renumber.
Email and App Compatibility
Older partners, payment platforms, and business tools still rely on direct IPv4 reachability. A stable block helps keep integrations steady and makes email reputation easier to manage over time.
Long-Term Cost Planning
For always-on services, ownership can beat multi-year lease costs. As of 2026, pricing near $25 per IP is common, though clean blocks, smaller blocks, and urgent deals can move that number up or down.
Plan Your Needs Before You Shop
A quick sizing exercise keeps you from overbuying, underbuying, or failing policy review.
List each public service, user group, NAT pool, and inbound system that needs direct reachability. Then project growth for 24 months, because ARIN reviews expected use, not just what you need today.
For global routing, plan to announce a /24 or larger. More specific routes are commonly filtered, so parts of the internet may never see them. Before you start, confirm your Org ID, your Registration Services Agreement status, and who can sign for the company.
If ARIN offers pre-approval for your request, use it. That step can shorten the final transfer once you find a seller.
Budget for the Full Cost
The quoted price per IP is only one part of the real bill.
Clean history, block size, region, and seller urgency all affect price. A /24 with a strong reputation may cost more per address than a larger block with a weaker history.
Add escrow fees, ARIN processing or membership costs, broker fees if you use a broker, and your own engineering time for routing, DNS, and monitoring. If you skip those items early, a fair deal can still break your budget.
Choose a Safe Buying Channel
The safest channel is the one with clear records, solid screening, and escrow support.
Marketplaces
Marketplaces can give you price visibility and a faster way to compare block sizes. Check how the platform verifies sellers, how it handles abuse checks, and whether it has a track record of completed transfers.
Brokers
Brokers can help with sourcing, negotiation, paperwork, and timing. Ask for sample timelines, screening steps, and a plain explanation of how they reduce the risk of title or abuse problems.
Private Sales
Private deals can work well when you already know the holder, but they still need the same controls. Use escrow, verify ownership directly in the registry, and document every step.
After you compare marketplaces, brokers, and private offers, focus on proof of ownership, blacklist checks, escrow handling, transfer paperwork, and who will keep the deal moving when timing slips or documents stall, including ARIN guidance, seller screening, and coordination through closing. If you want one place to review vetted options with that support, Brander Group’s buy IPv4 service covers ARIN guidance, seller screening, and coordination through closing.
Run Due Diligence Before You Commit
Ten careful checks now can save months of cleanup later.
- Verify ownership: Check RDAP or WHOIS, the public registry records, and make sure the legal entity matches the seller.
- Review abuse history: Check Spamhaus DROP and other public blocklists if you plan to send email or host customer traffic.
- Inspect routing history: Review past Border Gateway Protocol, or BGP, announcements for hijacks, unstable origin changes, or unusual paths.
- Confirm policy fit: Make sure the block size and region work under the transfer rules on both sides of the deal.
- Collect the paper trail: Ask for transfer records, chain of custody, and any Letter of Authorisation used during migration.
Use Escrow to Protect Both Sides
Escrow keeps money and control from changing hands out of order.
A normal flow is simple. Both sides agree on terms, the buyer funds escrow, the seller proves control, ARIN updates the record, and escrow releases the funds after the registry shows the new holder.
Straightforward deals may close in days, but two to four weeks is more common. Delays usually come from missing paperwork, slow signatures, or registry questions.
Follow the Transfer Steps Carefully
A clean checklist turns a stressful transfer into a routine operation.
- Get recipient pre-approval based on your 24-month need.
- Have the seller open or confirm the ARIN transfer ticket.
- Answer ARIN requests quickly and submit the required records.
- Pay registry fees and confirm the approved transfer size.
- Verify RDAP or WHOIS lists your organisation as the new holder.
- Release escrow only after that update is complete.
For an inter-RIR transfer, both registries must support the move and validate the same deal. Keep ticket numbers, approval emails, and signed documents together.
Get the Block Ready for Production
The transfer is only half done until the block is clean, secure, and routable. Layering in proper cybersecurity tools from day one helps protect your new space against abuse, hijacks, and unauthorised use.
- Coordinate BGP turn-up: Work with your upstream and announce only the aggregate you intend to use, usually /24 or larger.
- Publish ROAs: Create Route Origin Authorisations in ARIN’s hosted RPKI so other networks can verify the correct origin ASN.
- Add IRR records: Publish matching Internet Routing Registry objects and give any provider a signed Letter of Authorisation when needed.
- Fix geolocation: Publish an RFC 8805 geofeed, a simple file that tells databases where the addresses are used.
- Update operations: Set reverse DNS, refresh IP address management records, tune monitoring, and confirm abuse contacts on day one.
Conclusion
Good preparation makes this process predictable instead of painful.
If you size the block correctly, screen the seller, and use escrow, you can expand public reach without taking on avoidable risk. Start with policy approval, keep every document organised, and treat post-transfer routing work as part of the deal, not an afterthought.
FAQs
These quick answers cover the questions teams ask most before they move ahead.
How Long Does the Process Usually Take?
Most straightforward ARIN transfers finish in two to four weeks when pre-approval is already in place, and both sides answer quickly. Inter-RIR deals can take longer because two registries need to review the same transaction.
What Is the Smallest Block I Can Route Globally?
A /24 is the smallest prefix that usually propagates across the public internet. Smaller announcements are commonly filtered, so they are a poor fit for normal business routing.
Do I Need My Own ASN?
Not always. An Autonomous System Number, or ASN, gives you more routing control, but an upstream provider can announce the block for you if you provide a signed Letter of Authorisation.
How Do I Protect the Block After the Transfer?
Create ROAs right away, publish matching IRR records, and make sure your upstream prefix filters match your intended announcements. It also helps to monitor for unauthorised origin changes and keep your registry records current.
