If I put in a 30 notice to vacate before the end of my contract and the landlord enters into a contract with a new tenant (that I provided) to start the day that my contract ends. Can the landlord still keep my security deposit stating that I broke my contract.

Legally he probably can. The fact is you broke the lease. Even though you have made him whole, there are grounds for him to penalize you for breaking the lease. Whether that would hold up if you sued him, I'm not sure. Depends on where you are and how nice a judge you get.

Hello b:

No. The deposit it to safeguard against damage. It's not a windfall. If he doesn't return your deposit by the end of 14 days, sue him in small claims court.

Course, I don't know what state you're in. The above is general, therefore.

excon

If you find someone to move in, and the landlord accepts them, and there is no money loss at all, the landlord should be OK with it,
But then you may end up in court to be sure