Palmerston Island (IOTA OC-124) is a coral atoll lying approximately 500km north west of Rarotonga Island (IOTA OC-013), South Cook Islands, and 520km south of Suwarrow Atoll (IOTA OC-080), North Cook Islands.

Until April 2005 Palmerston Island counted for South Cook Islands for DXCC purposes.

In 2005, the ITU issued the E5A-E5Z callsign block to New Zealand specifically for use by the Cook Islands. The issuance of a callsign block to the Cook Islands changed its DXCC status to that of a Political Entity. As Palmerston Island is more than 350km from the remainder of South Cook Islands (approximately 360km from Aitutaki), Palmerston Island could no longer be considered part of South Cook Islands for DXCC purposes, and became part of North Cook Islands.

The DXCC mapping is summarised below:

ADIF Name ADIF DXCC No DXCC status Date Prefix Activations
South Cook Islands 234 Current Before 2005-04-02 ZK1 ZK1TW, ZK1SCQ
North Cook Islands 191 Current From 2005-04-02 E5 E51AND

More information on the above operations can be found by clicking on the callsign.

Below is the official ARRL statement on the subject:

"Cook Islands DXCC status changed (Apr 2, 2005) – Issuance of a call sign

prefix block for the Cook Islands has made them a DXCC political entity. "It

has come to our attention that the International Telecommunication Union

Table of International Callsign Series now contains an entry for the Cook

Islands," said ARRL Membership Services Manager Wayne Mills, N7NG. "New

Zealand has been issued the E5A-E5Z call sign prefix block for the exclusive

use of the Cook Islands. As a result, the Cooks become a political entity

for DXCC purposes." Mills says the impact on the DXCC List will be minimal,

however. "In reviewing the distances, it appears that the first 'separation'

from the South Cooks likely will be Palmerston Island, which is just over

350 km northwest of Raratonga," he explained. "The remainder of what has

been known as the North Cooks is not sufficiently distant from Palmerston to

become an additional DXCC entity." Mills says the main effect of the change

will be for Palmerston to count for North Cooks instead of South Cooks. The

change also may clarify a situation with the North Cooks. "Since the

addition of the Manihiki Islands (North Cooks) in January 1959 was not based

on a specific distance, Palmerston has counted as South Cooks," he said.

"DXCC Rule 5a comes into play now, keeping both North and South Cooks on the

list, but moving Palmerston to the North Cooks because it is more than 350

km from the South islands and becomes the first separation." Under the

circumstances, Mills said, it might now be appropriate to rename the entity

"Palmerston and the North Cooks."

Finally, as Palmerston is more than 350km from South Cooks, and more than 350km from the rest of North Cooks, one may ask why Palmerston doesn't count as an entity in its own right? To understand why, please refer to Find section 2. Geographic Separation Entity and then b) ii. As Suwarrow is 700 km from Aitutaki, the nearest of the S Cooks islands, and 500 km from Palmerston, the 800km rule applies. On this basis these N Cooks islands count the same as Palmerston, the nearest entity (and the first separation entity). 


Thanks to Roger Balister, G3KMA, and to ARRL