Offset mortgages are available in Great Britain and Australia, but have not been very available in the U.S., mainly because they somehow don't pass IRS muster. However, according to Money Magazine two U.S. companies have a version of the offset mortgage that passes IRS muster. The two companies are: CMG Financial Services and Macquarie Mortgages USA.
Macquarie Mortgages has several products which are similar to an offset mortgage. They seem to be based on a 30 year variable interest equity line of credit, where there are only interest is paid the first 10 years. Depositing funds into the mortgage and using their equity to pay monthly expenses keeps the principal balance lower, which reduces the amount of interest paid over the life of the loan and can also mean accelerated payoff.
CMG Financial Services has a product called Home Ownership Accelerator, which seems to be similar to the Macqarie Mortgages product. It is also based on a 30 year equity line of credit, where interest only needs to be paid during the first 10 years. Again you can make direct deposits or add funds. This reduces interest and accelerates payoff also.
These seem to be interesting alternative to a standard mortgage. Does anyone have experience with these type of mortgages and know of any other mortgage companies which have them.