At a Tax Deed Auction, if the high bid is more than the amount owed for back taxes, that amount is called an Overbid. This term is not necessarily interchangeable with surplus or Excess Proceeds. However, you will see counties using one or more of those words to describe ‘what is left over after the county is paid’.
The overbid amount does not belong to the county. The county takes only the property tax and interest owed and that amount is included in the opening bid. Therefore, as long as an auction gets a bid, the county is paid and the rest is the Overbid. The overbid is owed to Superior Lien Holders and the Previous Owner of the property (who owned the property at the time of the tax deed sale).