close a/the deal
To reach an agreement with another party, thus concluding negotiations. We need to move in a month, so how quickly can you close a deal and get our house sold? After months of negotiating, I hired a high-powered attorney to finally close the deal.
close a deal
and close the dealto formally conclude bargaining; to bring negotiating to an end by reaching an agreement. We negotiated the terms of the agreement, and this afternoon we will close the deal.