When someone clicks your ad the actual amount you’re charged will be.

When someone clicks your ad the actual amount you’re charged will be.

  • The minimum needed to hold your ad position under the maximum cost per click (max. CPC) limit.
  • The minimum needed to hold your ad position but never less than 50% of your maximum cost per click (max. CPC) bid, whichever is greater
  • The minimum needed to hold your ad position or 50% of your maximum cost per click (max. CPC) bid, whichever is greater
  • The minimum needed to hold your ad position, but never more that 120% of your maximum cost per click (max. CPC) bid.

Source: https://support.google.com/adwords/answer/2464960?hl=en