Cash at close is the part of the purchase price paid in cash on the day the sale closes, the most certain layer of the price.
In a sale
Because it is the most certain part of the price: two offers with the same headline can differ by millions in what the founder keeps, and the difference is in the layers above cash at close. An escrow, a seller note, an earn-out, and rollover equity each arrive later and depend more on the buyer. A founder decides which of those layers to accept before the first letter of intent arrives.
Where it comes up
The Go-To-Market Analysis (GTMA) builds the file a buyer would build on your business, before a buyer does.