Westpac and St George woud lead in mortgages

With a heavy bias toward New South Wales, a merged Westpac and St George would have Australia's largest mortgage book, exceeding $200 billion and more than a fifth of the market measured by outstanding mortgages by value.

The new entity will have a mortgage portfolio of $206 billion, as of March 2008, representing 21.1 per cent of the market.

This will surpass Commonwealth's $175.6 billion or 18 per cent market share as at March 2008. National would be the third largest at $146.6 billion or 15.1 per cent, with Australia and New Zealand Bank unchanged in fourth spot at $120.8 billion, or 12.4 per cent.

These estimates of market share are lower than those being quoted by Westpac, since the bank is estimating market share solely on the basis of APRA data that relates to bank lending only. The estimates used here derive from work published by InfoChoice and The Sheet in State of Play.

Still, these measures may soon align if the recent dominance of banks in the home loan sector continues.

For the year to March 2008 the major five Australian banks' combined mortgage book has increased 11.8 per cent to $648 billion, compared to the Reserve Bank's estimate for the entire industry of 11.2 per cent.