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Marly -
Tax coding is a guessing game. HMRC is a closed city and there are a few ‘rules’ that they don’t tell you about in the Tax Manuals.
Treat anything from HMRC with great suspicion; because there are lots of scams out there too. The answer to your first three questions is “Very Probably.”
.............. However ….
Is the £721 a demand from HMRC (paper P800) or your own calculation of tax owed ?
Are you registered for Self Assessment; ie do you have a UTR ?
Are you specifically required to submit a tax return each year ?
Have you set up an on-line Personal Tax Account with HMRC ?
Does your ‘empire’ includes earnings from another job, self-employment, property or overseas stuff etc ?
Where did you get your Coding 1331L from ? ....... Was it a paper P2 in which case it should have an explanation with it. ........... Or was it culled from your on-line PTA - in which case (for 17-18) it might be one of their rogue (they call it 'hypothetical' ) tax codes ?
Have you ‘gone paperless’ with HMRC ? (Big mistake btw)
A simple solution is to get yourself a reliable commercial tax programme for a few quid. I’ve used TaxCalc for many years. That way you can check everything out off-line and ‘in private’ and have lots of time to ask this sort of question, even if you don’t have to file a return. I would never use HMRC’s on-line tax programme for several reasons.
HTH .
............... LFH
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