(01-02-2021, 12:43 PM)mikesez Wrote:

(01-02-2021, 10:11 AM)Dockerill91 Wrote: Ah ok, the last part makes sense. I was getting confused then. Still secondary work income for us is just automatically taxed at 40% unless you’re a higher rate tax payer.

It’s very hard to Underpay here though, usually we find we overpay but even with that the HMRC do calculations every year and automatically refund us for simple things. Except the above things which I mentioned which are minimal.

In the US, your employer pre-pays an estimate of what you will owe over the course of the year.
But you are still obligated to fill the forms out and do the real calculation yourself at the end of the year.  Private services like TurboTax and TaxAct step in the gap and fill out the forms for you, but, in my opinion those guys are making money for nothing.  The IRS already knows what your forms should look like; they should just send them to you, and you can review them, and decide whether to agree and sign or whether to dispute something on them.