I have gone through the formal agreement procedures. I was on month to month terms and still have yet to receive any returnable funds. I was inspected and returned keys to premises on 15 Feb 2015, with rent prepaid. There was only praise of satisfaction with cleanliness and improvements. My last contact with previous landlord was 26 Feb 2015, Where he stated: "I'll send your deposit next week". No mention of return of unearned rent. I know the pro-ration formula and the 21 day deposit/complaint criteria... but I feel I am being blatantly ignored. Here I am in March (16th) no contact yet. BTW... previous place was immediately rented after my departure, which insinuates a Feb. 2015 contract signing. What do I do?

I know the pro-ration formula and the 21 day deposit/complaint criteria...

This is something out of the rental agreement, perhaps? Because, absent such contractual terms, one isn't usually entitled to have rent pro-rated.

It would be helpful to know what state or country you are in, but I would be calling them repeatedly, nagging them for the money which you think they owe you.

Any question on law needs your general locale as laws vary by area. We also need to know more of the circumstances. Did you give sufficient notice? Did you vacate on the notice date?

Many states allow for return of deposits within 30 days. That means postmarked, if mailed. The 30th day after 2/15 is 3/17. Ask back on 3/21.

The OP said; "and the 21 day deposit/complaint criteria..". So I'm gathering he is in an area with a 21 day deadline for returning deposits. If so, he may be able to sue for double or treble damages, since the deadline was missed.

The title of the thread is "Prorated rent refund", and OP writes that the LL made "... No mention of return of unearned rent ...". Thus it appears to me that OP is asking about a portion of the rent, not the damage deposit.