The world's top manufacturer of motor fuel from coal, said the exact amount to be raised would be subject to progress made on asset disposals and cost cutting.
Shares in Sasol fell 9.1% to 132.89 rand by 0711 GMT after announcing what could be among the country's largest rights issues in decades, potentially exceeding the company's market capitalisation of 91.99 billion rand.
Investors have been concerned by the company's debt, which has been exacerbated by delays and cost overruns at its Lake Charles Chemicals project (LCCP) in Louisiana and prompted the resignations of its joint chief executives to restore shareholder confidence.
Sasol on Monday reported a 91.3 billion rand ($5.3 billion)loss for the year to June 30, compared with earnings of 6.1 billion rand the previous year, hit by a 111.6 billion rand writedown on its chemicals and energy assets.
The company said total debt for the year stood at 189.7 billion rand, up from 130.9 billion rand a year earlier.
"Financial year 2020, which we indicated would be our peak gearing period, saw our stretched balance sheet come under significant pressure initially with the collapse in the Brent crude oil price to 21-year lows and then the onset of the COVID-19 pandemic," said Chief Executive Fleetwood Grobler.
Core full-year headline earnings per share fell 61% to 14.70 rand ($0.85) from 37.65 rand the previous year.
Earnings were also hit by 3.9 billion rand in depreciation charges and 6 billion rand in finance charges, Sasol said, adding that it would continue to suspend dividends to protect liquidity amid ongoing economic uncertainty.
($1 = 17.3624 rand)
By Tanisha Heiberg
