The National Suppression File (NSF) - database cleansing

The National Suppression File (NSF) is regarded as the definitive resource for gone away data by the DMA. The data is sourced from the Royal Mail National Change of Address (NCOA) file, the Gone away Suppression File (GSF), Electoral Roll changes and credible postal return resources.

The date helps reduce mailing inaccuracies by removing details of home movers and non responders.