I do different things for my state return versus my federal return. For my state return, I know with in a dollar or 2 what my tax liability will be by January 15th, when the 4th quarter estimated tax payment is due. I have zero taxes withheld from anything, so I simply pay the total taxes due, raising the amount to the next $10 multiple, rolling the remaining few dollars into the following year. Doing this means I won't have to provide any banking info on my paper return. I have an online account with the state, so paying estimated tax payments is pretty easy.
The federal return is more complicated, and I have done different things over the years and may do something different for 2026. There are too many uncertainties when the 4th quarter estimated tax payment is due January 15th. I don't get my 1099B until January 31st, so I don't know what my qualified dividends will be. Sure, I can estimate them, but some years I am not that close. Furthermore, in the years I get an ACA subsidy, I don't get the 1095-A form until after 1/15. I have tried, with varying degrees of success, to guess what the SLCSP amount will be, among other amounts I don't know beforehand. So, I just pay about half the total best-guess taxes due in January and the rest in April.
I used to have an online account with the IRS, but I lost it when they switched to ID.me and I lack the technology to set up a new account. I did get, for the first time, an IRS transcript for the 2025 year which shows what the IRS knows, including a record of my filed and received 2025 return which included an amount I happened to roll into 2026. I'm not yet sure what I will do for my 2026 taxes now that I am back on the ACA starting in July.