From FAQ on NINIS website:
Can I obtain a copy of the lookup table which links postcodes to geographic areas?
Yes - The Northern Ireland Central Postcode Directory (CPD) lists all postcodes and the geographic areas they are allocated to. The CPD is available for download in either Access 2000 or Text file (dollar ($) separated variables) format from the NISRA website. However, users must sign and return the Terms and Conditions document available here to receive a password for access to download CPD from the NISRA website.
Terms and conditions are available at cpdtermsconditions.doc.
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Northern Ireland Statistics and Research Agency (NISRA) Central Postcode Directory (CPD). No author.
Retrieved 23:31, May 19, 2013 (UTC).
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