My go-to first source is Yahoo! Finance’s “key statistics” page for any given company stock. There’s a “dividends and splits” section that lists a payout ratio. For example: https://finance.yahoo.com/quote/MCD/key-statistics?p=MCD
I find it’s generally reliable but not perfect. It tends to be slow to update after dividend changes and doesn’t always get the math right when a company’s dividend policy is to pay 1-3 “typical” dividends and then 1 “catch up” dividend to reach its targeted payout ratio for the year. In addition, it’s an automatic calculation that looks at payout with respect to earnings, so the numbers can look a little scary for companies like REITs and energy partnerships that pay their dividends based on cash flow rather than accounting earnings.
Regards,
-Chuck
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