Major banks are set to receive a funding boost over coming months as the country's leading superannuation funds reweight their investment portfolios to defensive assets such as cash and bonds. Big fund managers such as MLC and Australian Super are already reining in their respective exposures to equities in moves that should see some cash flow back to deposit products managed by the big banks. The strategic reallocation of assets within balanced super offerings of retail and industry funds could liberate up to $10 billion in deposit funding for bank lenders.Data published by the Australian Prudential Regulation Authority shows that deposits held at banks by superannuation providers and other financial organisations declined by $5.5 billion in the twelve months to the end of May as investment funds increased their holdings of equities over the period.The rotation into defensive asset classes is expected to occur across the superannuation market, with a swathe of small funds adopting even more conservative investment strategies than larger providers such as Australian Super."We're taking risk off the table," said Bill Watson, the CEO of First Super, which manages $3 billion of retirement savings."We're now increasing our exposure to cash." NAB economist Peter Jolly highlighted the impact that super funds might be having on the deposit bases of the banks, arguing the leakage from deposit accounts to other asset classes had contributed to systemic funding pressure. However, the expected net inflow of super fund deposits will go some way to easing the funding pressure that has intensified this year on local banks as benchmark rates for wholesale funding have risen.In the last week some of that pressure has also tapered, with the 90-day bank bill swap rate declining 10 basis points to 2.02 per centThe spread between the Reserve Bank's official cash rate and BBSW has narrowed to 52 basis points, a gap that still implies the market is expecting the cash rate to increase."It seems clear now that the lift in short term funding costs is something of a perfect storm affecting the Australian money market particularly," Jolly noted in his research report."BBSW has fallen further in recent days - 3 month setting yesterday at 2.02% relative to recent high of 2.12% - but BBSW-OIS spreads remains wider than USD or NZD markets."One factor that Jolly and other economists appear to have overlooked in assessing the 2019 funding gap of Australian banks is the likely impact of sliding house prices.If the property market correction persists for more than a year it will inevitably induce banks to cut their overall funding requirements.