The deadline applied to taxpayers submitting their returns electronically at a Sars branch, and to non-provisional taxpayers who used eFiling to submit their returns.

Sars spokesman Adrian Lackay said that more than five million tax returns had been received by yesterday, of which more than four million were for 2012 and 991 000 were outstanding returns from previous years.

“This represents an increase of about 22% in returns submitted if compared to the same period last year,” he said.

Yesterday alone, more than 96 600 returns were submitted. This was expected to grow to more than 100 000 by the end of today.

Lackay said heavy call volumes were expected at the Sars call centre. The centre would be open for assistance until 8pm.