You can tell TurboTax you plan to Pay by check. If you choose to, you can include the new balance (tax liability) in your current installment agreement. There will only be one installment agreement which includes all of the tax years that you owe. You should contact the IRS as soon as possible to have it included because a new balance will automatically default your current agreement (it is one of the terms and conditions.) You can call them at 1-800-829-7650 or go to a local office.
