Contact
Email is the only channel. Corrections are read first.
Write to [email protected]. Every message is read. Replies take longer than a live chat would, so for anything urgent about an open position, your broker's support line is the right place to call.
Corrections
Include the page address and the sentence, figure or step you think is wrong. For a worked example, say which line of the arithmetic you get a different answer on. Confirmed errors are fixed on the page and the updated date changes, as the editorial policy describes.
Questions and suggestions
Questions about how a metric is calculated or how a calculator works are welcome, and so are suggestions for metrics or research tasks that are not covered yet. Browse the metrics and how-to guides first, since the answer may already be there.
Getting a useful answer
A question about a number is easiest to answer when it comes with the numbers. If a calculator gives a result you did not expect, send the inputs you typed and the output you got. If a quote page shows a figure that disagrees with a metric page, say which field it was, what the page's own label or tooltip calls it, and the date you looked. Most mismatches come down to the period the figure covers or whether earnings are reported or adjusted, and those two details usually settle it.
What cannot be answered
Requests for advice on a specific stock, trade or account cannot be answered. Nobody here knows your situation, and a reply would amount to personal financial advice. The risk disclaimer explains why. For questions about a broker account, contact the broker; for a complaint about a registered firm, FINRA and the SEC both take complaints from investors.
Companies offering products for review: the buyer's guides name no providers, so there is nothing to submit.