Here in the US, at least; I don’t know how you crazy people in other countries do it.
The damage this year:
Federal: Got back a whopping refund due to overestimation of what we’d owe this year, and immediately ploughed it back into the IRS, because when you’re self-employed, you have quarterly estimates due on top of anything else you owe. Yes, being self-employed sucks sometimes. But at least it’s coming out of money the IRS already had, rather than from the bank account.
State and local: Owed negligible amounts, paid without complaint.
In all, fairly painless.