We set up automatic withdrawal through turbo tax to pay tax due on April 18, 2016. We want to pay it earlier. How do we do that?
Once your return is accepted, you can't change any of the payments details, but, you can cancel the electronic withdrawal payment and use another payment method.
You can call IRS e-file Payment Services anytime at 1-888-353-4537, 7 to 10 days after your return was accepted to cancel your payment.
You must cancel your payment 2 business days prior to the scheduled payment date.
Check out "Cancellations, Errors and Questions" from IRS link below "Pay Taxes by Electronic Funds Withdrawal"
You can also pay your taxes electronically after e-filing using this IRS link: https://www.irs.gov/payments