That makes sense, they just pass the debit fee on to you. However e-check is an ACH transaction. I've never seen any online payment site that charges for e-check as I believe there isn't an individual transaction fee associated to ACH.

Just because your debit card is connected to checking, doesn't mean that if you pay by e-check it automatically invokes the debit fee. It's only if you pay via the debit method, eg if you don't want to give our your true account number for some [wrong] reason.

I am absolutely certain there is no charge as this is the one and only way I pay taxes, and like you I would mail a check if there were any fee at all attached to e payment.

Ah now I remember why I don't file electronically.

For estimated taxes to NY it only allows "direct debit from bank account" which is classified on Wikipedia as:

"A direct debit or direct withdrawal is a financial transaction in which one person (or company) withdraws funds from another person's bank account."

I don't like the idea of the government having direct access to my bank with an ability to pull funds whenever they choose to.

I don't disagree with the sentiment, but the government already has this ability, whether you pay electronically or not. When you write a check, the money is in fact transferred electronically, just with a paper authorization as middleman. Do you know you can write any date whatsoever on the check and it doesn't matter? Also the amount can be completely illegible. Doesn't matter. Writing a check isn't any kind of "defense" against the thing you don't like. I don't believe the tax authorities accept cash, but I may be wrong. That would be your only way to limit their reach.

If "direct debit" incurs the fee, then yes, I too would write a check. Not sure from the description if that is functionally equivalent to e-check or ACH, or if it means the same as "debit card".

Avoiding the fee is useful, but avoiding the reach is impractical and not achieved with a check.