Last-minute shopping for Christmas has produced an electronic transactions speed record on Saturday but the biggest day is likely to have been Friday.

Traditionally Christmas Eve is the busiest day for retailers, except in years when it falls on the weekend when Friday tends to set records.

The busiest 15 seconds in retail shopping in New Zealand occurred at 11.45am on Saturday, says Paymark, which handles more than 75 per cent of the nation's Eftpos terminals.

The peak usually happens between 12.30pm and 1pm but this year it was a bit earlier.

The number of daily transactions exceeded the five million mark on December 21, 22 and 23, a first for Paymark, and the final figure for December 24 is also likely to be more than five million transactions.

This Christmas Eve won't be the biggest shopping day of the year with that honour falling to Friday, Paymark says.

Christmas Eve Eftpos:

• Peak second with 171 transactions at 11:45:45
• Peak hour with 543,538 transactions from noon
• Peak minute with 9.389 transactions at 12:20pm