The Four Toll Free Area Codes: 800, 888, 877, and 866.

Since 800 numbers are the most coveted and the most recognizable, they are often the most difficult to obtain. And while the others are widely known as toll free, in some instances when advertising, you may decide to take the time to remind consumers that 888, 877, 866 numbers will cost them nothing. In other words, if you are wary that some of your potential customers may not recognize the 866 pre-fix, write “Call Toll Free” in bold letters before the number to clear up any uncertainties.

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