In an action to foreclose a mortgage, plaintiff appeals from so much of an order of the Supreme Court, Suffolk County (Kelly, J.), dated September 24, 1982, as denied its motion for leave to amend its complaint to add a cause of action to foreclose another mortgage and to amend its reply to defendants' counterclaims to include certain affirmative defenses. Order reversed insofar as appealed from, without costs or disbursements, and motion granted on condition that plaintiff pay defendants $250 costs. Plaintiff shall pay the costs within 20 days after service upon it of a copy of the order to be made hereon, with notice of entry. The amended pleadings shall be served within 20 days after such payment. In the event the payment is not made, then order affirmed insofar as appealed from, with costs. CPLR 3025 (subd [b]) provides that leave to amend pleadings should be freely granted on such terms as may be just. Although plaintiff waited an inordinate period of time to seek leave to amend its pleadings, defendants have alleged no actual prejudice and "[m]ere lapse of time, unaccompanied by proof of actual prejudice to the defendant, is not a sufficient ground for denial of such a motion" ( Brewster v City of New York, 78 A.D.2d 667). Plaintiff's motion should therefore be granted. However, plaintiff did not attempt to explain the extreme delay which may necessitate further discovery and a postponement of the trial of this action. The imposition of costs is therefore justified. Lazer, J.P., Mangano, Gulotta and Niehoff, JJ., concur.