When you refinance your mortgage you will be essentially taking out an entire new mortgage with different terms and conditions and they'll be a document preparation fee as well as a loan origination fee.
The amount of those fees will depend on how much your mortgage is for.
But lets say your mortgage is for a $200,000.00 home, the origination fee would be somewhere around $2,000.00
The origination fees are usually around 1% of the total cost of your loan "mortgage" amount.
And the document preparation fees range from $200.00 to $900.00 and the fees can vary from bank to bank and from mortgage to mortgage but that's about what it costs to refinance your mortgage.