The buyer makes a written offer through his agent to the listing agent on May 15. The listing agent delivers the offer to the seller on May 16. The seller signs the offer as submitted on May 17 and delivers the signed offer to the listing agent on May 18. The listing agent emails the executed contract to the buyer’s agent on May 19. The buyer’s agent calls the buyer on May 20 and informs the buyer that the seller has accepted the offer.
The effective date in this example is May 19, the date the listing agent communicated to the buyer’s agent that the seller signed and unequivocally accepted the buyer’s offer.