A payment extension just gives you a little more time to pay your bill before your next bill payment is due. All you need is a copy of your bill details handy to apply.  

Once your payment extension is granted, Synergy will not charge a late payment fee if you pay your bill by the new extended due date, However, if you don't pay your bill by the new extended due date, a late payment fee will be charged (and added to your next bill). 
 
Apply for a payment extension