If you mean for this tax year then you just need to get your tax credits/deduction card sorted out and it should balance out automatically. If you mean for one of the previous four tax years then you need to write to Revenue with details of your P60 and maybe even a Form 12 return to get things balanced for the year in question. If you were ever self employed/assessed then the procedure may be different and you should ask your accountant.
If an employer subjects you to emergency tax, they will then refund you the excess tax deducted when they receive your proper tax credit certificate.
If a person is on emergency tax at the end of the year, they are likely to have overpaid tax for that year and should send their P60(s) to the tax office for a refund.
My last question is:
If i'm self-employed with two main separate activities and one is losing money and the other is not can i offset losses from the first in calculating my taxes from the second?
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