Green card holders must pay US tax on their worldwide income and pledge that the US is their forever home.
After the Treasury had initially refused to comment, it has now emerged Mr Sunak gave the card back in October last year, having become chancellor in February 2020.
A spokeswoman for Chancellor said: “Rishi Sunak had a green card when he lived and worked in the US.
“Under US law, you are not presumed to be a US resident just by dint of holding a green card. Furthermore, from a US immigration perspective, it is presumed that permanent resident status is automatically abandoned after prolonged absences from the US.
“At the same time, one is required to file US tax returns. Rishi Sunak followed all guidance and continued to file US tax returns, but specifically as a non-resident, in full compliance with the law.
“As required under US law and as advised, I have continued to use his green card for travel purposes. Upon his first trip to the US in a Government capacity as Chancellor, he discussed the appropriate course of action with the US authorities. At that point it was considered best to return his green card from him, which he did immediately.
“All laws and rules have been followed and full taxes have been paid where required in the duration he held his green card.”
Rishi Sunak defends wife Akshata Murty over non-dom tax status as allies ‘blame …
The Prime Minister had earlier insisted Mr Sunak had done “absolutely everything” required after reports first emerged.
He told a Downing Street press conference: “As I understand it the Chancellor has done absolutely everything he was required to do.”
Boris Johnson also denied No 10 has been briefing against Mr Sunak over his wife’s non-dom status.
“If there are such briefings they are not coming from us in No 10 and heaven knows where they are coming from,” the Prime Minister told a Downing Street news conference.
“I think that Rishi is doing an absolutely outstanding job.”
Naomi Smith, Chief Executive of better democracy campaign group, Best for Britain said: “This latest revelation about the Chancellor leaves the country asking, did the taxman pay his taxes?
“British voters are suffering from his complete mismanagement of the economy and his punitive tax hikes, and it shouldn’t take a foreign government to point out that a UK minister should pay tax in his own country.” Earlier Douglas Ross urged the Chancellor to be “open and upfront” about his wife’s tax arrangements.
The Scottish Tory leader said Mr Sunak must answer questions about Akshata Murty’s non-domiciled status, adding it was “right that these issues are raised”.
Ms Murty, the daughter of an Indian IT billionaire, was paying £30,000 a year to claim non-domiciled tax status despite living in Downing Street.
Speaking on Friday, Mr Ross said: “In terms of what the Chancellor has said to date on this issue, I think he has tried to clarify the situation with his wife’s status.
“And it’s clear, as we continue, that other issues come up and I think it will be right for the Chancellor to respond to those very quickly, to provide the clarity that everyone would expect on this issue.”