IP Address Blocks ARIN Issues From

ARIN IPv4 Address Blocks

ARIN (or its predecessor registries) have performed allocation and assignment of IPv4 address blocks from specific address blocks assigned by IANA. The list of IPv4 address blocks is available here on the IANA website.

ARIN’s free pool of IPv4 address space was depleted on 24 September 2015. As a result, we are no longer fulfilling requests for IPv4 addresses directly from a free pool. All approved IPv4 requests are placed on our waiting list for unmet requests. There are exceptions in special cases outlined by policy, such as:

  • NRPM Section 4.10: This IPv4 block is dedicated to facilitate IPv6 deployment. Organizations may request a /24 of IPv4 address space to facilitate its IPv6 deployment if the following criteria are met:
  1. The applicant may not have received resources under this policy in the preceding six months, except to the extent that the applicant is requesting resources for a discrete network in respect of which it has not received any resources under this policy in the preceding six months;
  2. Previous allocations/assignments under this policy must continue to meet the justification requirements of this policy;
  3. Previous allocations/assignments under this policy must be utilized to at least 80% to obtain an additional allocation or assignment; the applicant must demonstrate that no other allocations or assignments will meet this need.
  4. An applicant requesting multiple allocations under this policy to support Multiple Discrete Networks, as defined under NRPM Section 4.5, may not receive more than the equivalent of a /21 of IPv4 address space in any one six-month period hereunder.

ARIN also facilitates IPv4 transfers and maintains a listing of transferred address space.

ARIN IPv6 Allocation Blocks

List of IPv6 prefixes that have been set aside for ARIN to allocate from.

  • 2001:0400::/23
  • 2001:1800::/23
  • 2001:4800::/23
  • 2600:0000::/12 [1]
  • 2610:0000::/23

[1] ARIN is issuing IPv6 transitional technology blocks from 2602:0000::/16. For more information, please see NRPM Section 6.5.3.1.

ARIN IPv6 Assignment Blocks

List of IPv6 prefixes that have been set aside for ARIN to assign from.

  • 2620:0000::/23