Depending on when the house will close, holidays and at the end of the month is the busiest time for Title companies. Once the sale's transaction is recorded, the title company overnight the docs to the mortgage company, and your first installment date may depend on how quickly the docs are overnighted and recorded by the lender.
At the end of closing, usually before you leave the Title Company, the escrow agent will provide you mortgage payment instructions, when the first payment is due.
The lender will also be able to provide you with the date of your first installment payment.
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