Returning IP addresses & ASNs

Internet resources (IP addresses and AS numbers) assigned directly by LACNIC may be returned if the organization holding the resources no longer wishes to use them.

Resources assigned by ARIN or by the central registry to organization in the region prior to the creation of Regional Internet Registries (RIRs) may also be returned to ACNIC.

Resources may be returned for a variety of reasons, including cessation of business, merger with other organizations, network restructures, and others.

Once it has been returned to LACNIC, the organization previously holding the resource will no longer be allowed to use it. In addition, the resource's registration information will be removed from LACNIC's Whois database.

Internet resources returned to LACNIC may later be assigned to other organizations.

How to return IP addresses or ASNs

  1. The organization's administrative contact must complete the following form.
  2. Sign the corresponding document (Document for returning resources assigned directly by LACNIC, Document for returning resources assigned by ARIN) Example 1, Example 2
  3. Sign the document and send it to LACNIC, Rambla República de México 6125, Montevideo, 11400, Uruguay
  4. Once an organization has submitted the formal request, it will be evaluated by LACNIC, who may request additional documentation. LACNCI will only accept requests to return resources from organizations with no outstanding balance.
  5. If you have any questions, please get in touch with us at the following addresses: If your organization has an outstanding balance with LACNIC, contact facturacion [at] lacnic [.] net. If the registered contact no longer works at the organization, contact hostmaster [at] lacnic [.] net

If returning a block of IP addresses, the prefix of the block to be returned must be:

  1. Equal to the assigned prefix; or
  2. Half the size of the assigned prefix, provided that it is not smaller than the minimum assignment size under the policy currently in force for the type of assignment involved (ISP or End User).