Are you the kind of person who meticulously goes over the receipt to calculate the tip amount or do you just tack on what’s suggested at the bottom? Perhaps you should reconsider.

According to Readers Digest, those percentages are one of the sneaky ways restaurants can overcharge you.

Normally people will leave 15-20 percent on the table, but many of the printed amounts start at 18 and climb to 25. More so, it’s based on the post-tax total.

RD quotes the Emily Post Institute, who they call, “the grandmother of all etiquette.” According to them, 15 to 20 percent of your meal price pre-tax is correct.

How do you calculate the amount to tip? In which situations is it ok not to leave a tip? How about when taking food out?

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