No, there is not a fee for paying a bill online as long as you pay using your bank account after signing in to Your Account.
However, if you pay your bill with a debit or credit card, or use One Time Access to your account (which does not require you to create a username and password), you will be charged a convenience fee of up to $1.35 per payment, based on card type.
Why there’s a convenience fee for card payments
PG&E has partnered with an independent payment provider to provide you the option of using your credit or debit card to make payments on a one-time or recurring basis. Each transaction incurs a processing cost. The convenience fee is charged by an independent payment provider. California Assembly Bill 746 (AB746, enacted in 2005) does not allow energy companies, including PG&E, to pass on these costs to all customers. Only customers who choose to use this service will be charged the convenience fee.
Why there are different convenience fees ($1.00 vs. $1.35)
Credit card convenience fees are $1.35 per payment. Debit card convenience fees are either $1.00 or $1.35, depending on which payment network is used to process the transaction. The actual fee paid will be stated in the payment confirmation page.