All of the major credit card companies removed the signature requirement in April 2018. There is no reason that any card processor or merchant should still require a signature almost two years later.
Menards required signatures for any size credit card transaction up until about nine months to a year ago. I believe they removed the requirement entirely now as I spent several hundred dollars multiple times recently with no signature required.
For Debit cards, but not Credit cards. The latter will often have a PIN system if one wants to get cash advances at ATM machines, but I've never had a system yet ask for a PIN on a Credit transaction in any establishment. It's either insert(CHIP most common now) or swipe with some systems still requiring a signature.
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The most expensive tool is the one you buy "cheaply" and often...
I suspect that the reason that some merchants are still requesting them is because they are using outdated equipment or have something setup incorrectly with their processor. Or is may be an odd-ball processor that hasn't updated things. Almost every time I've been asked for a signature, it's been at a small merchant or because of the nature of the transaction. (pharma, etc.)
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The most expensive tool is the one you buy "cheaply" and often...
I was in the U.S. earlier this year and in the UK last week. All purchases over $35 in the U.S. with my U.S. chip and pin credit card required a signature. All credit card purchases in the UK with the same card required a signature, regardless of purchase price. When I used my German chip and pin debit card in each country, no signatures were required.
Other than restaurants, every merchant I go to uses a card reader that uses my chip card and no signature required. If the reader takes your chip card (not swiping) and requires you sign the pad the merchant hasn't upgraded. I haven't seen the old readers in a few years around here.