Two New South Wales credit unions are exploring a merger, the largest in the mutual banking sector so far this year.Summerland Credit Union and Coastline Credit Union last week advised members the two boards had "signed a Memorandum of Understanding to explore the potential benefits a merger between the two credit unions could provide to their respective members."Coastline (based in Kempsey) and Summerland (based in Lismore) serve overlapping target markets in northern NSW.  If they merge, they will have 16 branches "from Coolangatta in the north to Taree in the south."With combined assets of more than A$1.2 billion, and above system loan growth at both mutuals, the new organisation will be around the same size as Australian Military Bank, sitting just outside the top 20 in mutual ADI rankings.The boards propose to maintain both the Summerland and Coastline brand names with, as yet, no mention of any interest in following the fashion to take up "mutual bank" branding. In its 2018 annual report, Nicolas Harrison, chair of Summerland wrote that the board "has no plans at this time to become a Bank, by name or structure. "Your board remains to be convinced of the benefits," he said.