If she is to travel here to stay for less than 6 months then should would not normally need to apply for a visa before she left because they are granted at customs to NZ citizens, but she should have evidence of the money available to her (eg. bank statements), travel insruance and details of her return journey.
If she needs to stay for a longer visit then she will have to apply directly to the UK embassy in NZ for a 1 or 2 year visa. If doing this she would need you to execute a sponsorship declaration in which you state the terms of the visit, that you shall accomodate her and pay any unforeseen expenses of her stay here so that there will be no need to access public funds.
She cannot undertake paid or unpaid work whilst in the UK on a visitor's visa. This is very important.
If she wishes to work her then she could apply for an Ancestry Visa, which are granted for five years. She will qualify if she can show that:
- shge is a Commonwealth citizen (passport)
- you are aged 17 or over (passport)
- She has a grandparent who was born in the UK (grandfather's birth certificate + passport if available)
- She is able to work and intend to do so in the UK (job offer, or evidence of jobs she can do)
- She can support yourself and any dependants without needing any help from public funds (eg. evidence of salary she would earn, evidence of her personal savings, evidence of your savings/bankstatements if you are to write a sponsorship declaration on her behalf.
Again, she would need to do this by applying directly to the UK embassy in NZ.
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