Abstract: The present invention relates to a method, system and platform for money market mutual fund purchasing for cash management. In particular, it relates to facilitating book order entry transactions for cash managers that have multiple banking relations and that diversify their cash management by purchasing money market mutual funds from multiple unaffiliated providers. The technology disclosed supports electronically receiving instructions that select among the unaffiliated providers' products, electronically issuing binding orders and binding transfer instructions for settlement, and using SWIFT messages to confirm the transfers to the cash managers. The cash managers' instructions may be received in a variety of forms. In some implementations, this technology is extended to reconcile balances and holdings after execution of the orders and transfers, and to flag any discrepancies.