With so many 1116 limitation options, you'd be forgiven for some head scratching on which basket actually aligns with a certain income. The vast majority of those 1116 limitations that we'd use would be:
'Re-sourced by Treaty', - fairly straight forward, - U.S. sourced income.
'Passive' Interest income for example
'General' Earned income for example.
There is a grey area between the 'Passive' and 'General' category though and there has been much head scratching by me in trying to figure out if lottery winnings are passive or General. (only a 'few' quid) also certain none benefit income such as Carers Allowance that is fully taxable in the U.K. Certainly not earned income and i'd think more 'Passive' as it's not a job? U.K Pension, is that General or passive? Annuities are shown to be Passive in the instructions - So does that mean if you have regular pension drawdown it would be classed as General, but a retirement annuity would be Passive? (more head scratching)!
With multiple categories, I don't think that a credit in one can help towards the others. For example, you can't use a $100 credit in Re-sourced by Treaty' category to cover a $50 shortfall in the 'Passive' category. All categories seem to merge on the 1116, but is that $100 'Re-sourced by Treaty' going to age out, despite being of benefit elsewhere?