Can you cancel a co-op contract before the closing date ?

of course not. He has a legal contract to purchase and has agreed to close.

Tell your friend to talk with a lawyer ASAP.

As others have said, the contract is the guiding document. You say the co-op 'is not ready' which implies that he cannot close through no fault of his own. That may be his get out of jail card.

Otherwise, he might try a trick that can work; co-op contracts have to be written that they are subject to board approval of the buyer and his finances. This process includes a face to face interview. It is not that hard to make yourself unattractive enough to be declined.

He can back out but will not get his deposit back.

You'd have to read the contract to find the cancellation clause. The deposit may have been non-refundable, partially refundable, or completely refundable. Does the contract state a completion date? If it does and they have not completed it, he may be able to get out from under it completely.

Read the contract itis legally enforcable and your 'friend' needs to understand his/her legal liabilty, at the very least your 'friend will not get their money back, there may be a buy out clause in the contract, ( read and see) if not then your 'friend' is obligated to the terms of the contract for the full time of the contract

Not having seen the sales contract, no one here can be sure. Usually, however, the sales contract will say that if the buyer backs out he/she forfeits the deposit (it acts as a deterrent since the seller lost money taking the unit off the market). In a worst case scenario, your friend can get sued by the seller and a court may rule he has to follow through. It takes both sides to change or cancel a contract. Closing date papers are irrelevant - it is teh sales contract that is paramount.

He will likely forfeit his deposit. Depending on the wording of the contract, he may also be held liable for breach of conract and any cost associated with such.

I have no idea what one is. iN The us, co-ops are participating credit unions that let you share branches.

generally, deposits are non refundable. They are to bind you to a deal.