Generally speaking, you can change the closing date in your residential real estate contract with consent from the other parties. There may be repercussions for this change, as well as fees and additional costs for one or both sides. Your ability to change might also depend on your contract.
Closing contracts take a lot of work to finalize. It can seem like, once finished, they are set in stone. However, nothing is truly final until both the buyer and the seller close the deal by signing the document in good faith, from an informed position and of their own free will.
As explained on Realtor.com, your contract probably provides some leeway in terms of changing the final deadline for your deal. If your agreement is anything close to standard, you probably have a clause that sets a closing date alongside a typical conditional statement: that an agreement between both parties can change the date, for example.
The key concept here is “agreement”. As long as your communications are cordial and your requests are reasonable, most minor delays should not endanger an otherwise solid deal.
However, getting consent of the other party in the transaction is only one concern. You should also consider any agreement you have with your lender. Some loan issuers offer rates specifically based on your closing date. Any delay could incur fees or other consequences, depending on the agreement you have with your bank.
You may also want to consider property taxes. You will only pay property tax on a home if you own it. Therefore, you are liable based on the date the home changes hands. Depending on the amount in question, you may find it advantageous to address this issue when negotiating for a change of closing date.