I was in New Zealand on a working holiday visa in early 2017 for about nine weeks - across the last few weeks I was there, I did some remote software development work for a few different clients, all located outside of New Zealand. I earnt roughly ~$800 USD gross in total for this work.
I live in the United Kingdom and continued doing freelance software development work upon returning to the UK in May as a self-employed contractor. I am having to wind up my software development work and need to sort out what tax I need to set aside for the end of the financial year.
Do I need to pay income tax on the ~$800 USD to New Zealand, or would it count as part of my UK income?
There is a double tax agreement between New Zealand and the United Kingdom, and New Zealand's IRD website states for independent contractors:
most DTAs may exempt you from income tax in New Zealand if you are in New Zealand for less than 183 days and you do not have a fixed base or permanent establishment in New Zealand.
I was only in New Zealand for ~70 days with no permanent base, so I think I am meant to pay tax only to the UK - does this sound reasonable?