Legal Question in Landlord & Tenant Law in Florida

Your lease controls whether payments are timely or not. You have to abide by the terms of your lease agreement. If you have a 5 day grace period and receipt is required by that date, then payment on the 6th day is late. Impossible to answer your question as phrased. The mail box rule, which means getting it in the mail timely, will not likely protect you unless the lease provides for the funds to be mailed.

Typically rent must be received on or before the due date in your lease agreement. Most leases have a "grace period" (say 5 days for example). Making the due date is your responsibility, not the responsibility of your Bank. Try not to let a couple of days of delay result in a tenant removal proceeding. If your landlord is being ugly you might suggest that you pay him a VERY small "late fee". Better this than becoming immersed in litigation.

Disclaimer: The facts of every case differ and your question does not address all the possible issues. You need to consult counsel. If counsel fees are prohibitive you can call your local county legal aid organization for free or minimal cost advice. I hope everything turns out fine for you.