Cash rounding or Swedish rounding occurs when the minimum unit of account is smaller than the lowest physical denomination of currency. The amount payable for a cash transaction is rounded to the nearest multiple of the minimum currency unit available, whereas transactions paid in other ways are not rounded. Cash rounding typically occurs when low-denomination coins are removed from circulation owing to inflation. Cash rounding may be a compulsory legal requirement if such coins are no longer legal tender, or a voluntary practice where they remain in circulation but are scarce or impractical.
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