> I contacted the tax office to see if my tax credits would increase due to our circumstances, but they say no, as my wife had already transferred the max to me.
If you were already on joint/aggregated married taxation then the standard rate cut off point (SRCOP) and tax credits would have been allocated as appropriate - e.g. on the basis of the split requested or, more likely, with €19K SRCOP allocated to your wife as the lower paid and the remaining €37K SRCOP allocated to you with the relevant tax credits (some of which are not transferrable) allocated to each individual. If it turns out that, for one reason or another, you would have paid less tax through a different allocation of SRCOPs/credits or due to other events (e.g. your wife leaving work) then this will either be taken care of through adjustment of your SRCOP/tax credits and payroll calculations or else through a reclaim for any tax overpaid after the end of the tax year.
These Revenue resources might be of use to you:
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This calculator might help to get an idea of what your tax and PRSI/health levy liabilities are in different situations.
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