The naira plummeted at the parallel market from N510/dollar earlier on Wednesday.
Dealers in Lagos Island sold the greenback at N516 and bought same for N513.
The situation was the same at Murtala Muhammed International Airport, Lagos.
Naira had traded at N507/dollar on Monday and Tuesday on the black market.
Demand for dollars has soared even though the external reserves have reached $29bn.
The naira continues to trade flat at the official interbank window at N305.5 to the dollar.
Traders said demand pressure was on the black market but dollar supply had not improved, as sign of looming further depreciation of the Naira.