Q. How can I distinguish telemarketing calls from those calls I want to answer—before I pick up the phone?
A. Caller ID will provide some clues: When it displays "Call Center" or a charity's name, it's most certainly a telemarketer. "Private" or "Undisclosed" could signal a privacy-seeking acquaintance, but unscrupulous telemarketers also like to hide where they're calling from. Others feign legitimate corporate affiliation (such as your credit card company) by using so-called spoofing services that put a fake name on your caller ID screen.
When I'm not sure, I let my answering machine take the call. Telemarketers rarely leave messages. When they get no answer, they typically move to the next number on their calling list. My real friends and family leave messages, as do legit businesses calling about account issues. (Occasionally scammers pretending to be representing those companies will leave you a message and a call-back number that will link you up to them—so for any return calls, always dial the toll-free number on your statement or card.)
If you do end up on the line with a telemarketer, it's of course always possible to end things promptly with a polite refusal, a request to be taken off the telemarketer's list and a hang-up.
But when harassed by repeat calls, I often opt for the following response: "Hold on while I get the better phone in the other room." Then I go about my business, leaving the caller dangling. Result: After a while, the caller hangs up and doesn't call back. Telemarketers usually have per-hour or per-shift call quotas and they can't waste time waiting.
Sid Kirchheimer writes about health and consumer issues.