When do I lock my mortgage rate after an accepted offer?

Locking a mortgage rate after an accepted offer is a decision for the buyer's loan officer, based on market conditions and how close the closing date is, since a lock typically expires after a set window and needs to cover the full underwriting period. Locking too early risks expiration before closing, while waiting too long risks a rate change. Brian recommends buyers talk with their lender the day the offer is accepted.