"I will act this week, but not tomorrow," Quinn said on Monday.
It's believed the Illinois governor will sign the bill passed by a 32-25 state Senate vote in January to abolish the death penalty in the state. The Illinois House also approved the measure.
"The governor continues to deliberate," spokeswoman Annie Thompson said late Friday.
If Quinn signs it, Illinois would be the fourth state since 2007 and the fifteenth altogether to rid its books of capital punishment.
After the Senate passed the bill, SB3539, it wasn't immediately clear what Quinn would do with it.
The Chicago Democrat supports the death penalty but he also has continued the long-standing moratorium on executions.