Johannesburg - Taxpayers must submit their returns by the end of Friday to avoid penalties, the SA Revenue Service (Sars) said.
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 spokesperson Adrian Lackay said that over five million tax returns had been received by Thursday, of which over 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.
On Thursday alone, more than 96 600 returns were submitted. This was expected to grow to more than 100 000 by the end of Friday.
Lackay said heavy call volumes were expected at the Sars call centre. The centre would be open for assistance until 20:00.
Sars branches would be open until 16:00.
* Sars eFiling
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