An unrestricted investment account is a type of account in Islamic banking in which the customer authorises the bank to invest the funds in any way it sees fit, without limits on the kind, place or period of investment. The usual contract is mudarabah: the account holder supplies capital, the bank acts as manager, profits are divided in an agreed ratio and financial losses fall on the account holder unless the bank was negligent or breached the contract. The funds are normally pooled with the bank's own money.
These accounts are the main Islamic alternative to interest-bearing savings and term deposits. Unlike a deposit, neither the capital nor a return is guaranteed. In practice banks smooth payouts using a profit equalisation reserve and an investment risk reserve, to keep returns competitive. The contrasting product is the restricted investment account, where the customer specifies how funds may be used. Standards issued by AAOIFI govern their accounting.