While this is in line with other recent surveys showing direct mail volumes are waning, Royal Mail's figures contradict indications that financial clients have been cutting down on direct mail.
Its survey shows that banks increased their direct mail volume by 5.9% from 73.42m in the second quarter of 2005 to 77.78m in the second quarter of 2006.
Julie Stephens, head of financial sector marketing at Royal Mail, said: "Banks continue to recognise the benefits of using direct mail as a way to build their brand and create customer loyalty by educating their customers on their products and services, as well as to actually drive sales."
The survey also found a "significant lift" in the overall volume of direct mail sent to 55- to 64-year-olds, and in volumes sent by automotive and charity sectors.
Automotive sector volume rose 12.3% to 12.32m items and charity sector volume rose 10.5% to almost 97m.
Earlier this year, the Direct Mail Information Service put direct mail volume for the whole of 2005 at 5.13bn, down 5.3% on 2004.
Last week, the DMA's Email Marketing Council repeated its prediction that email volume is set to match direct mail volume by the end of 2006 after first-quarter email volume grew 30% in a year.
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