A profit-sharing investment account that is subject to a specific set of conditions as specified by the account holder. In other words, the provider of funds (depositors) place restrictions on how the Islamic bank (as depositee) will use their funds to finance and/ or invest in specific projects or assets. Due to such restrictions, the funds of special investment accounts (SIAs) are managed separately (i.e., as a standalone source of funds not commingled with other sources). Restrictions include venues of investment, degree of risk (mukhatarah), geographical area of investment, etc.

The term “special investment account” is particularly used in Malaysia. In the Arabian region (e.g., GCC), it is known as restricted investment account (RIA).