Yes, you can make additional One-Time Payments even if you have Recurring Payments.
- After logging into your account, click the red Make a Payment button
- Select your Primary Payment Method or select Add New... and then click Continue
- Enter your charges, and click Add Charge. Once you have added all your charges, you can proceed to click Continue.
- Verify your charges and click Confirm. The next page will be your receipt, which you will also receive by email.