security deposit not returned

Landlord still have not returned sec deposit and it has been 45 days. One excuse after another. Do I have to sue? is it not illegal for him to do this?

Some states allow up to 60 days to return this deposit. Since we don't know where you live, we don't know if they have violated this or not. Please post your state for specific advice.

Go back to your lease. The lease supercedes the law in your state. So if the LL is supposed to return the deposit within 30 days it doesn't matter if the state says 45 or whatever. You may need to pursue in court.

A written contract cannot overrule state law. (And we don't even know if the lease said 30 days.) If your state law says the LL has 60 days to return the deposit, that's the amount of time he has. The OP needs to list the state so we can let him know how long the LL has to return the deposit.

A few other issues:
Did you provide a forwarding address in writing? Some states' laws say that your failure to provide this information negates his responsibility to return the deposit.

Did you return the keys to the unit? Retaining keys is tandamount to retaining possession of the unit. The deposit is nt due back until a period of time AFTER the LL regain possession of the unit. Keeping the keys means you never gave him back possession.

Did you give proper written notice to vacate? Failure to give proper notice can leave you owing rent for this period.

If you have folllowed all the above steps, send a written demand for the entire deposit's return to the LL by certified mail, return receipt requested, and keep a copy for your records. If he still doe not comply, you will have to sue him in small calims court for its return.