Can we send saving statement less frequently than quarterly? Like semi annually or annually?

We haven't had our hands slapped yet, but we send savings statements twice a year. We continue to pay interest quarterly.

Unless you have accounts that are EFT-activated, you can send statements as often or infrequently as you like (unless you have a state law controlling). And if you send them out less frequently than quarterly, you don't have to comply with the statement specifications in Regulation DD.