There are a few important dates in the dividend process.
Dividend payments follow a chronological order of events and the associated dates are important to determine the shareholders who qualify for receiving the dividend payment.
Announcement date: Dividends are announced by company management on the announcement date, or declaration date, and must be approved by the shareholders before they can be paid.
Ex-dividend date: The date on which the dividend eligibility expires is called the ex-dividend date or simply the ex-date. For instance, if a stock has an ex-date of Monday, May 5, then shareholders who buy the stock on or after that day will NOT qualify to get the dividend as they are buying it on or after the dividend expiry date. Shareholders who own the stock one business day prior to the ex-date—that is on Friday, May 2, or earlier—will receive the dividend.
Record date: The record date is the cutoff date, established by the company in order to determine which shareholders are eligible to receive a dividend or distribution.
Payment date: The company issues the payment of the dividend on the payment date, which is when the money gets credited to investors' accounts.5
Please note, per FINRA and the SEC all US equities trades settle 2 business days after the trade date. This settlement period is commonly referred to as T+2.