Mostly, as in the gist of what he's saying is true.
The UK system of PAYE is much more precise than the US system of withholding. If all you have is your job, then yes, no additional tax is due and no refund is due.
You are required to file if and when:
>You have additional income which may be subject to tax.
>You are requested to file by HMRC.
You may want to file something anyways (either a Self Assessment form or a briefer rebate request form (I'm not sure of the name of the form)) if and when:
>You have reason to believe they owe you a refund.
Sometimes PAYE isn't done quite right in the first year on a job. There's an "emergency" PAYE code that overwithholds. This is occasionally used upon arrival at a job, and reverts to a normal coding once the new tax year begins. If you had an emergency code, you may be due a refund. Check it out if you're not sure.
You would need to speak with someone who knows your whole situation very well to confirm whether or not any of your overseas income is subject to tax in the UK. This is because taxation of your overseas income depends on domicile, remittance, moving date, and treaty issues that are far, far to lengthy to get into here.
Caveat: I myself am not a UK tax licensed person (though I have collegaues who are).
