IPv4 addresses are still in short supply, and many teams need more space to support growth. Buying IPv4 space can be sensible, but a transfer involves paperwork, policy review, and routing security. This guide explains how to size a purchase, check the rules, protect the transaction, and secure the address space after it lands in your account.
Map what you really need before you buy
Start with need, not sellers. A clear forecast keeps costs under control and makes routing simpler.
Right-size your block
Most teams start with a /24, which includes 256 addresses. It is typically the smallest block that routes cleanly on the public internet, so buying less can create operational headaches. Sketch a one- to two-year growth plan, then include an IPv6 path so you are not relying on IPv4 purchases forever. Public IPv6 adoption has continued to rise, which makes dual-stack planning a practical requirement for many networks.
Understand the ground rules by region
Each regional internet registry has its own transfer policy. If you are a U.S.-based buyer, you will most likely work with ARIN, but the differences matter when suppliers, records, or network sites sit elsewhere.
ARIN transfers in plain English
For ARIN transfers, recipients generally need to document use of at least 50% of the requested IPv4 space within 24 months. The transfer request must come from an ARIN Online account linked to an Admin or Tech point of contact for a valid Org ID. The source organization must also provide a signed and notarized Officer Acknowledgement Letter. Watch the waiting-list rule as well: IPv4 received from ARIN’s waiting list cannot be transferred for 60 months, except for 8.2 mergers and acquisitions transfers.
RIPE specifics
In the RIPE NCC region, IPv4 addresses and 16-bit ASNs cannot be transferred for 24 months after receipt. RIPE’s waiting list allocates recovered IPv4 space in /24 units, and only to LIRs that have not had a previous allocation.
A safe buying checklist worth bookmarking
Use this order to reduce legal, financial, and routing risk before the transfer starts.
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Verify the seller’s authority. Make sure WHOIS or RDAP records match the selling entity, that the company still legally exists, and that any merger history lines up with 8.2 transfer requirements.
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Screen the block’s reputation. Check the addresses against blocklists such as Spamhaus and Talos, and confirm the range is not special-use, reserved, or bogon space. IANA’s IPv4 registry can help you confirm allocation status.
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Confirm size and hold-period risk. Re-check the ARIN 60-month waiting-list rule and the RIPE 24-month rule so a hold period does not surprise you later.
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Agree contracts and escrow terms. Make sure the agreement defines inspection steps, rejection rights, registry approval triggers, and when funds are released. Some escrow processes release funds once WHOIS lists the buyer, so match the contract to the registry workflow.
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Submit transfer tickets correctly. Both sides file their paperwork, and officers should be ready to sign the required acknowledgements without delay.
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Verify and document after approval. Confirm the updated WHOIS and RDAP records, then save copies for auditors and your incident-response runbook.
If the address purchase is part of a wider infrastructure change, document why the space is needed, which applications depend on it, how hosting, storage, backups, and analytics may change over the next year, and who will own the operational follow-up after approval. Use that inventory alongside broader planning notes on cloud database choices.
Post-transfer routing security you should not skip
Owning the addresses is only half the job. The other half is making sure the internet trusts your announcements.
Create ROAs with RPKI
A Route Origin Authorization, or ROA, confirms that a prefix holder authorizes a specific autonomous system to originate routes to that prefix. Create one for each prefix you announce, and set the max-length to match any planned de-aggregation.
Create authenticated IRR objects
ARIN provides a GUI and an API to create IRR route and route6 objects, and its FAQ outlines the steps. Some upstream providers may also ask for entries in RADb, so confirm what your transit partners require.
Timelines and what to expect
A clean transfer is mostly waiting between short bursts of activity. Agreements, payment, transfer submission, registry verification, approval, and funds release often take days rather than weeks, but review times vary. Inter-registry transfers or legacy records can add time.
Budget signals and market context
Prices move, so treat any figure as a market snapshot rather than a quote. Recent market reporting has shown average prices around the high teens to low twenties per IP, with larger clean blocks, region, timing, and reputation influencing the final number. Ask for current comps, but do not treat public averages as a promise for any specific deal or provider.
Where to get help with provider-neutral options
You can run a transfer yourself, but a facilitator can handle policy compliance, documentation, escrow coordination, and blocklist remediation. Brander Group is one firm that operates in this space, and it appears in ARIN’s Qualified Facilitator directory, which signals ARIN-vetted transfer facilitation status. If you prefer a provider-neutral advisor to compare options and manage steps across ARIN, RIPE, and APNIC, you can review Buy IPv4 services that support policy-compliant transfers.
Put it into your network plan
Once the addresses are live, fold the upkeep into operations. Add ROA and IRR maintenance, route monitoring, and IP address management to your runbooks. Assign clear owners and service levels so nothing drifts. If you worked with Brander Group or another facilitator, complete records will make future transfer reviews faster and easier.
Conclusion
Buying IPv4 safely comes down to a few disciplined habits: size the block to real need, learn your region’s rules, verify the seller and the addresses, protect your money with sound escrow terms, and lock down routing security right after the transfer. Build dual-stack and IPv6 readiness into the same plan, and you reduce both future spend and future risk. Work the checklist, document everything, and the process becomes routine rather than stressful.
FAQs
What is the smallest block most teams consider?
A /24 is often the practical starting point because smaller blocks may be harder to route on the public internet.
Why does the registry region matter?
Each regional registry has its own transfer rules, documentation steps, and hold periods, so the process can change based on where the records sit.
What should be checked before payment releases?
Confirm authority, reputation, contract terms, escrow triggers, and updated registration records before treating the transfer as complete.
What happens after approval?
Update operational records, create routing security objects, monitor announcements, and assign owners for ongoing maintenance.